Seed Production in Petrocosmea

As I continue to harvest that last seedpods from this winter's Petrocosmea hybridizing adventures, I find myself, one again, feeling excited and grateful that I've had success in producing seeds from my favorite genus of gesneriads. For years, around ten to be exact, I consistently failed to produce even a single seed..or a seedpod either for that matter. But, at least I was consistent! One of the most requested tidbits of information I receive is for advice on how to produce seeds in Petrocosmea. I thought I would outline my process here on the blog.

First, let me say that this is what works for ME, in MY environment, with MY plants. Other growers, in other conditions, may have very different results. I don't suggest that I am an expert, only that I've been lucky for a short time now, and this is what worked for me. While I have shared this with other accomplished growers in the recent past, I have heard from only one person who was successful in producing seeds. There are others, who've had success, of course. Other well before I had luck. Mr. Nakayama, in Japan, in fact, produced the first Petrocosmea hybrid around a decade ago... P. 'Momo'...the result of a cross between P. nervosa and P. flaccida. He has since remade the same cross and produced two selections..P. 'Asa Blue' and P. 'Imperial Butterflies'. Mrs. Joyce Stork, here in the US, produced introduced two hybrids a couple of years ago, P. 'Fluffer Nutter' and P. 'Short'nin' Bread' both from a cross between P. forrestii and P. flaccida. And Mr. Jeff Foerderer of the Netherlands, had produced a number of crosses recently. He registered two of them with the Gesneriad Society....making these the first registered Petrocosmea crosses. Those were P. 'Lexi' and P. 'Milan'. So we are beginning to see some success with hybridizing Petrocosmea. To date, I have been successful in producing seeds from a total of 22 seperate hybrid crosses over the past three years. Most of those, 14 of them, produced during this past winter.

So what has worked for me? Well, the key factors for me, which I have tested and proven during the past two winters, have been a combination of high humidity during flower production and seedpod maturity, and cool to cold temperatures. If either of these factors was changed or missing, I have had total failure in the crosses. Furthermore, I must say that those same two factors have been proven critical to successful seed germination as well. But first, lets get the seeds and then we can discuss how to germinate them.

So here are the steps I follow to produce seeds:

1. The seedpod parent must be flowering in high humidity...100% if possible. As plants come into bud, I enclose the whole plant inside humidity domes over the nursery trays on my lightstand shelves. Also the area should be cool...around 40 degrees F. A bit cooler is fine...I've had successful pod formation in 38 degrees F and as warm as 50 degrees, but no warmer.

2. Select flowers for pollination that are at least four days old. Older is fine as long as the pistil and stigma are still in good condition. Around the time the flower is about to drop seems the best, but the stigma is usually not receptive until around four days.

3. Select pollen from the freshest flowers you can find...freshly opened up to three or four days seems optimal. Pollen should look "fresh and fluffy" dry dusty pollen does not work for me. Frozen or refrigerated pollen has also failed to work for me too. I use a simple process of collecting the pollen on my thumbnail from the anthers so that I can see it easily. "Pack" as much pollen on each stigma as you can get it to accept.


This photo, taken by my friend and master hybridizer Dale Martens, shows the reproductive structures of a Petrocosmea flower. Note that the stigma at the tip of the pistil is purple. The filaments supporting the anthers have furry white hairs.

4. Label each flower pollinated. I use a small square of paper with a hole in the center and a small slit on one side to allow it to be slipped onto each flower peduncle. I also record the parentage and date of the cross in a manual which I keep all of my hybridizing records in. This becomes a most valuable resource later on.

This photo shows seedpods forming on P. forrestii. Note that after successful pollination, the tip of the pistil dries to just below the stigma. the ovary swells quickly and pollination will be evident in around 8-10 days after making the cross if it has been successful. These seedpods are about one month out from pollination.

5. Wait. This is the hardest part. Ripening for me has taken 60-80 days with around 64 days being the most common. I have had successful germination from seeds taken from a pod that was only 49 days old, when the mother plant began to deteriorate and I was afraid of loosing the cross. Generally, though, I wait until the seedpod browns and is just beginning to split open. Seedpods will split from the base upwards along two sides of the pod. The seedpods appear to have two chambers.

Another excellent photo taken and shared with me by my friend Dale Martens, shows Petrocosmea seeds. Viable seeds appear plump while non-viable seeds appear more linear and smaller.

6. Once the seeds are ripe and harvested, I sow them immediately. I only sow a small amount of the seeds and freeze the rest. I sow seeds on moist, fine vermiculite or moist peat moss pellets. I enclose the seeds once planted and keep them moist with high humidity. In the same temperatures used for seed production...around 40 degrees F, I get germination in 14-28 days from fresh seeds. Once seeds are a bit older, I find germination takes longer, and it has taken as long as 3 months on older seed. Seeds sown in warmer temperatures have consistently failed to germinate for me and several other growers with whom I've shared seeds for testing.

Once seeds germinate, I begin to fertilize them with a weak solution of water soluble fertilizer at a rate of 1/8 - 1/16 teaspoon per gallon of water. I keep them under lights in the same conditions the mature plants grow in.

Once the seedlings are large enough, I transplant them into community pots and treat them just like the mature Petrocosmeas in every way. Of course, labeling and careful record keeping are maintained at every step of the way. The photo above shows seedlings at about three months from germination.

Again, cool temperatures and high humidity are what have made the critical differences for me. I hear often from growers who have tried repeatedly to cross Petrocosmea and failed. When I ask about the conditions in which they attempted the crosses, one or both of these factors always seems to be missing.

This year, I tested this several times by attempting crosses in lower humidity and in warmer conditions. I had NO success. Only when both factors were present did the crosses take. Even then, with the two critical factors in place, my success rate with total attempts remains under 50%. I make sure to pollinate around ten to twelve flowers each time I make a cross. Sometimes I get as many as 7 seedpods, other times, I may get only one. And of course, sometimes I get none. But, the challenges are what makes this so much fun and so rewarding once those seedlings finally do bloom. This is part of what fuels my passion for these magnificent creations of nature! One thing that alway occurs 100% of the time though, is that I learn something every time I try a cross. And I have fun 100% of the time too!

A Silky Haired Trio - The Petrocosmea sericea Group - III

Should our trio become a quartet? In the last two posts, I have been discussing the three plants that I place with a group I call the "Sericea Group". This is my own placement and terminology around the three plants labeled P. sericea, P. sp. 'HT-2' and a newly collected plant labeled P. sp. ?'JR2008-1'. But, should this trio include one more plant? Study the photo below in comparison to these photos of the flowers on these three plants from my last post.

Very close isn't it? I think so. Morphologically, the flowers and foliage of the plant I acquired last year labeled P. cavaleriei are so very close. I have sent plant material to have it's DNA studied in relation to the DNA of the other three, but do not yet have results. Hopefully those will come soon. But, independent of the DNA data, I feel this plant belongs to the same group as the other three. It does not totally match the published description of P. cavaleriei, but then neither does P. sericea.....or most other Petrocosmeas which currently bear a name. Again, the identity crisis for this genus.
The flowers of P. cavaleriei closely match those of P. sericea and the others in the "Sericea Group". It clearly fits within the Section Anisochilus, as do the other three plants. Other than form of the petals, it is identical.

Petrocosmea cavaleriei pictured above, looks very much like P. sericea, and P. sp. 'HT-2'...especially the latter. It differs only in it's small stature. This plant stays small, after two years, this plant still remains in a three inch pot. Cymes are single flowered. I'm anxiously awaiting the DNA results to see how closely it is related to the others in this group.

I thought I would conclude by showing a bit of what P. sericea is capable of as a parent in hybridizing. My very first hybrid, pictured above, is the result of a cross using P. sericea as the pollen parent with P. rosettifolia #3. The hybrid was named for a dear friend, P. 'Rosemary Platz'. It inherited a heavier leaf substance, the leaf shape, and size from P. sericea. Flower size and coloration on this hybrid also show the influence of P. sericea. The serrated leaf edges, the glossy green leaf color with lighter yellowish veins clearly came from the P. rosettifolia parent.

A close up of the flower of P. 'Rosemary Platz' shows a nice lavendar color from P. sericea, while the absence of the dark purple blotch at the base of the tube, along with the two yellow stipes are from the P. rosettifolia parent. Flower size is similar to P. sericea.

A trio of first flowers from three seedlings resulting in my second P. sericea cross. This time P. sericea was the seed parent with pollen coming from P. minor veined leaf form. The variation in the purple color of the flowers shows the lightest being the color of P. sericea and the darkest coming from the deep purplle of P. minor. Two flowers have the white throat of P. minor, while the one on the left has no white in the throat...which is most like P. serice. All three inherited the deep purple blotch at the base of the corolla, which both parent have. Genetically, P. minor and P. sericea are closely related to each other. None of these seedlings have been named as yet, but the three pictured are held for another years growth to evaluate their perfomance as they mature. While P. sericea can be slow to mature, these three all bloomed as tiny plants in one ounce pots.... each seedling flowered with fewer than ten leaves.

A Silky Haired Trio - The Petrocosmea sericea Group - II

In the last installment, I discussed the foliar characteristics of the trio of plants I call the "Sericea Group" due to the fact that they all share very similar foliar and floral characteristics. In addition, recent DNA data shows all three plants to be closely related to each other, so close, in fact, that they may be simply three unique individuals within the same species.

In this post, I would like to focus on the characteristics of the floral morphology. I'll start with the first plant to come into culitivation... the plant we currently grow as P. sericea.


The flower of P. sericea shows characteristics which clearly place the plant within Section Anisochilus, having shorter upper petals, one half the length of the lower petals. The flowers typically have five petals, with the shorter upper two petals being fused into a two lobed "hood" which bend forward over the pistil. The anthers cup together to form a "beak" with the pollen ejecting from the pointed tip of the "beak" when pressure is applied to the wider base of the anthers. P. sericea's flowers are usually born singly on the cyme, with a nice bluish lavendar color. At the base of the tube inside, is a darker purple spot. The petals on P. sericea are a bit longer and narrower in the lower portion of the corolla.

The cymes of P. sp. 'HT-2' are often multi-flowered...having from 1 to five flowers...most commonly two or three flowers. The petals on the flowers of this form are shorter and rounder at the lower portion of the corolla, giving a "fuller, rounder" look to the flowers when compared to P. sericea's flowers. Coloration is identical on the two forms.

The lower three petals of the flowers of P. sp. 'HT-2' are rounder and shorter than those of P. sericea, giving the flowers a fuller appearance. In this photo, you can barely see the darker purple spot at the base of the corolla around the ovary of the pistil.

While my own plant of P. sp. ? 'JR2008-1' has not yet flowered, this photo shows the plant from which my plant was propogated. The calyx lobes on this form appear hairier and more silvery, when compared to P. sericea and P. sp. 'HT-2', but the flowers otherwise appear nearly identical. Like P. sp.' HT-2' this plant appears to have multiple flowers on each cyme. This photo also shows the more open form of the rosette on this form and also that the leaves are softer adn have a less succulent nature than the other two forms in this group. The leaves are more pliable and softer to the touch.

A close up shot of the cyme and flower of P. sp. ? 'JR2008-1' shows the longer, more silvery calyx and cymes on this form...an attractive feature in my opinion. I look forward to the flowering of my plant, which so far, has been slow to flower.

While the flowers are very similar, there are key differences which allow each form to be identified as unique in it's own right. Still, I feel these are all representative of the same species. Time will tell.

There is one last installment in this series....... Should Petrocosmea cavaleriei be included in the "Sericea Group"?

A Silky Haired Trio - The Petrocosmea sericea Group - I

In my continuing quest to know the genus Petrocosmea better, I've been focusing lately on a trio of plants that I call the "Sericea Group". Why do I call them this? Well, because these three plants are yet more of our wonderful Pet species which are currently victims of the identity crisis that plagues this genus. Only one currently has a species name attached and even that one may be incorrectly attached to this plant. That species, Petrocosmea sericea (pictured below) is the first of the group to come into cultivation in the USA, and this is the name applied to it from that time until today. So, I use that one,being the first and the only one with a species name, as the species around which I "lump" the other two plants...those being Petrocosmea sp. 'HT-2' and Petrocosmea sp. ? 'JR 2008-1'. These three plants are the focus of this short series.

So, what do I know about these three beautiful species? Well, the do all appear to be very closely related to each other....perhaps even three forms of the same species. The early DNA analysis does place them very closely related to each other, but three clear distinct individuals. In other word, they are not the same individuals...the DNA is a bit different, but they may be the same species. My personal opinion is that they are. Morphologically, they are very close also.

Secondly, they do appear to fit within the Section Anisochilus of the genus. Morpholically, the flower's anthers and corolla easily fit the defining characteristics to fit within that section. This section also includes the plants we currently grow as P. rosettifolia, and the P. minor (s). If you grow all of these, think about the flower structure and you can easily see that aside from size and color, the flowers are shaped almost identically in may respect. These all have the two upper petals that are shortened and bend forward, fused into a "hood" at the top of the flower. The flowers of the plants in the "Sericea group" all are nearly identical, with the only differences being that sp. 'HT-2' has a branced cyme with 1-5 flowers per cyme, while P. serciea most often has a single flower per cyme. I have not personally flowered the P. sp. ? 'JR 2008-1', but have seen photos of the flowers, which appear almost identical to the flowers of the other two species. All three plants have silvery hairs on the calyx lobes and cyme, making it appear silvery, frosted and silky.

Third, the leaves of all three species are similar, with the following differences. P. sericea has the most succulent leaves of the three plants, with the margins curled up forming a "spoon", which to my eye, is very attractive. The margins of the leaves of P. sp. 'HT-2' curl downward
in the opposite manner of the leaves of P. sericea, and are a bit smaller than the leaves of P. sericea, but are otherwise identical. The leaves of P. sp. ? 'JR2008-1' are the "thinnest" and softest of the three, and are clearly the largest of the group. They are softer to touch and more flexible. The "silkiest" if you will. This form also forms the most "open" rosette of the three plants. All three plants offset rarely for me, and tend to grow slowyly. The newest of the three.. sp. ? 'JR2008-1' grows the slowest of all. The plant pictured below is now nearly two years old and still is a small plant.

Petrocosmea sericea - the first of the group to come into cultivation around 2003. It is "close" to the published description of this species, although the published description mentions the hairs being golden or yellowish... the hairs on this plant are clearly silvery and "white". Otherwise the description is pretty close. I have to wonder if the description might have been written using dried or preserved plant material to describe, and perhaps the hairs turned more yellow or golden with age and drying? I have collected some leaves to press and dry in order to see if the colors of the hairs changes with age and drying.

The leaves of this plant cup upward and are the heaviest substance of the three...being quite succulent. This plant grows slowly, compared to all other species I grow, and makes a spectacular rosette as it ages. Two years, minimum, seems required to get a "mature" plant from a leaf propagation. The plant only gets better and flowers more heavily with age.
It also tolerates and seems to appreciate a bit of drying between watering and the leaves spoon more and look more silvery with higher light.


A comparison of two mature plants of P. sericea and P. sp. 'HT-2'...both of these plants are in 5" pan pots and are three years old when this photo was taken. They were grown side by side with identical culture to test the differences in the two species. Note that P. sericea, (left) is more silvery in appearance and the leaf margins cup upward forming a spoon. The leaves of P. sp. 'HT-2' (right) are greener in appearance and the margins are flat or curl downward. Leaf size is close, with the leaves of P. sp. 'HT-2' being a bit smaller on the average.

The newest species in the trio is one labeled P. sp. ? JR2008-1'. It came to me from a friend who got it from the collector in China in late 2008. This plant grows slowly. The plant in the photo above is two years old, and is still in a 3.5" pot. It has not yet flowered for me, but I have photos of the flowers which I will post in the next post on this group. The plant in all respects is very close to the other two morphologically. Leaves are much larger than the other two plants, even on this young plant. I currently have six smaller plants that were propped from this plant as "insurance" and to share with other Pet friends so that we can begin to get this form into broader cultivation. I am also sending a plant to a botanical garden as part of the collection there. It is always exciting to get new genetic material and new forms of Pet species in cultivation.

This photo shows the leaves of the three forms discussed in this post, for comparison. They are (Left to right): P. sericea (left), P. sp. 'HT-2' (middle) and P. sp. ? JR2008-1' (right).

These three plants add beautiful and interesting diversity to the family Petrocosmea in any collection. There is no other Pet that has the characteristics of these three. While P. nervosa and P. flaccida also have the silvery, silky hairs covering the leaves, the flowers of these are quite different. P. flaccida and P. nervosa have floral characteristics that place them within Section Petrocosmea of the family, while these plants clearly fit into Section Anisochilus. Additionally, the DNA data suggests that these three plants are very closely related to the group of P. minor(s). The"minors" are their closest relatives, according to the DNA. I have been successful in crossing P. sericea with P. minor veined leaf, when P. minor would not cross with other species. This willingness to hybridize with the minors suggests a close relationship also.

In the second installment on this topic, I will focus on the flowers of these three plants.

Petrocosmea Hybridizing - Harvesting Seeds

Having tried to successfully pollinate Petrocosmea flowers hundreds of times over a period of tens years, it is difficult to describe the joy of being able to say "I'm harvesting Petrocosmea seeds today!" This is my third annual seed harvest and the crosses this year have me excited about the potential for attractive, new foliage and flower characteristics...and maybe even some new colors or at least new "shades" of color. This season, so far, if my counts are accurate, I've applied pollen to 323 flowers. I've collected 21 seedpods so far, all with seeds inside, although some had a precious few seeds. I accuse me of being a bit of a fanatic about Petrocosmeas, I guess. But it is harmless fun and very exciting. I'm learning so much about this genus.

So what am I learning? Here are some observations about hybridizing Petrocosmeas and successful seed set. First, I must say again, that for me, the two key factors in my success, I believe, are making the crosses and allowing the flowers and seedpods to develop in cool temperatures (cold by some definitions) and high humidity....(100% if I can get it). Most of the failures this year, also served to prove this point for me. The early bloom season this year began in summer, when we were quite warm. The plant room was in the mid-70's F. The plants were growing out in the open shelves with the humidity at about 60%. All of those attempts failed. I did get seedpods to form on some P. begoniifolia flowers that were covered, but again they were growing in warm temperatures. All of those seedpods were empty when they ripened. As the plants continued to flower, and the temperatures began to drop with the arrival of autumn, I did not begin to have success until November 29, when I made several crosses in temperatures in the 40's F and most all took! These plants were all enclosed inside my humidity domes, so humidity was 100%. Since then, with the cool temps, I've had nearly 90% success with all species EXCEPT the P. minors...which still refuse to be seedpod parents. I have limited success with this species as a pollen parent and got one more cross this year with P. minor veined leaf form as a pollen parent onto the species P. rosettifolia #3. That was it. Excluding this species, I'm now having excellent results with high success rates if I observe the rules above.

In the photos above and below, you see the seedpod of Petrocosmea rosettifolia #3, which I feel in many ways, is the showiest of all of the forms of this species. The seedpod ripened in 62 days and was FULL of seeds, which can be seen in the second photo below. The seeds are large and plump, so I'm hoping they germinate! This exciting cross using P. rosettifolia as the seedpod parent and P. minor veined leaf form as the pollen parent, was made in the hopes of getting the darker green, and bright yellow veining of the leaves of P. rosettifolia #3 crossed onto the highly glossy, deeply veined leaves of P. minor veined leaf form. Also, I'm hoping that the purple flowers of minor will get some of the deep yellow in the throat of P. rosettifolia #3. I'm also hoping the ease with which P. rosettifolia #3 accepts pollen and sets seed will come through in fertile progeny to be used for further breeding. Who knows what I'll get, but then, therein lies the fun of hybridizing!

A bountiful seed harvest from P. rosettifolia #3. Other forms of this species are reluctant to hybridize or self. This form is almost always successful as a both a pod and pollen parent. Note that the seedpod splits along opposite sides from tip to base.

The large, showy, snow white petals of P. rosettifolia #3 surround a bright lemon yellow throat. Happily, it is a great parent. Flowers on this form are the largest of any form of P. rosettifolia.

The mother plant of the seedpods shown above. This photo was taken on the day that I began to make crosses with the plant. I'm hoping that the deep green, yellow veined, and glossy leaves come through in the hybrids. This form also is reluctant to form offsets, whereas other forms of the species form them quite readily. Flowers are large and showy, and present in an attractive fashion over the well-shaped crown of leaves....In many ways, a perfect parent for hybridizing.

The pollen parent of the cross which produced the seedpods above. This is the flower of P. minor veined leaf form..... a fragrant flower! This species has consistently been reluctant to serve as a pod or pollen parent with other Petrocosmeas, or it's siblings, or when selfed. It just doesnt' want to cross. Likely, the problem is that I have not yet discovered some peculiarity about it's fertility. You can bet that I'll keep trying. It has been successful as a pollen parent only twice before....crossed onto P. sericea, P. forrestii, and now P. rosettifolia #3. I'm hoping that the latest cross will infuse some yellow into the clean white throat of this flower for some tricolored flowers in the next generation. If it passes the fragrance along, I'll be happy with that too!!

Other things I've learned..... Petrocosmea crosses seem to take a minimum of 60 days for seedpods to ripen. A couple of crosses have taken up to 80 days to ripen. The two top species for successful crosses have been the prolific little P. forresttii in the number one spot, and P. rosettifolia #3 in the number two spot. P. sericea and sp. 'HT-2' would be in the number three spot. All of these have been successful in most all of my attempts to use them as parents. This year, I tried P. parryorum, which bloomed for me with lots of flowers. Not one attempt was successful, and I tried! Believe me I did~~!!! Attempts to use P. parryorum as either pod or pollen parent were all unsuccessful. The pollen was often rotted. I'm wondering now, if perhaps this species does not like the high humidity to pollinate? I'll be trying again next year with plant in both the uncovered and covered areas to see if by lowering humidity I preserve the pollen and maybe have some success? P. kerrii was also unsuccessful, in all but one attempt. Again, little P. forrestii came through for me and produced two tiny seedpods with a few seeds....Now if they will only germinate. P. begoniifolia seems to be the most flamboyant species for producing full, round flowers, with nice ruffling and coloration on the petals. I've used it in several crosses this season in hopes of some breakthroughs in the flowers.

One last observation that I'll mention about hybridizing. Use flowers that have been open for at least four days. It seems to take that long for the pistil to enlongate and the stigma to be mature and receptive. I've gotten to the point that I can tell by looking at the stigma when it is mature. Use pollen from freshly opened flowers, as it seems to lose viability quickly in the high humidity. But, it loses viability much quicker in the low humidity...high humidity rots it, low humidity dehydrates it. I tried storing it in the refrigerator and the freezer...so far, no success using stored pollen.

SO, a fun day, harvesting seeds and getting filled with the anticipation of the new Petrocosmeas to come along as these seeds begin to grow and show their stuff! Stay tuned.......

And you MUST try hybridizing!

Winter's Wonders

Winter is a beautiful time of year here in southwestern Pennsylvania. The icy scene outside the window of my upstairs sunroom from a couple of weeks ago as we were under the effects of one of the coldest periods in the area since the 1700's is a testment to the wonders of nature. (The largest of those icycles are over 5 feet long!) While the temperatures dipped outside, I have been using the time to work with my gesneriads inside. It was a great excuse to stay indoors and enjoy those other wonders of nature - Petrocosmeas!

I decided to post some random comments about what was going on in the plantroom. While we are squarely in the middle of winter here, I am seeing the final days of the flowering season for the Petrocosmeas. This has been an atypical season for flowering this year. Usually, the Pets begin flowering for me in October and conclude around March. This year, they began flowering in early August! P. barbata, as usual, was the first to flower, and P. duclouxii and P. sp. 'Yumebutai' are rounding out the season as the last to flower...again, it is typical that these are the last, but they are much earlier than normal. We had a cooler and wetter summer, much cooler and wetter, last year, so I feel that the lower temperatures during the summer triggered an earlier season for the Pets.

The last of the seedlings from the P. 'Asa Blue' x begoniifolia cross are now blooming. The one above I had pulled out of the batch and named P. 'Keystone's Whipporwill'. It produces a large flower, with wide petals, giving the flower a nice, full appearance. The petals have a ruffling and notching that I find different and pleasing. This photo actually shows the color accurately, but the focus is poor...I apologize. The photos with better focus had the coloration all wrong. Many of the flowers show extra petals too, as does this one. I am evaluating it another year or so, and will perhaps release it if it meets my two main criteria....heavy flower production, and a reluctance to form offsets. So far, it looks quite promising. The negative is it's long peduncles, from the 'Asa Blue' parent. It was grown in low light this year, so I hope that with better light, they will be shorter and heavier. They did always support the large flowers, so that is good, but I just wish they were a bit shorter for a neater presentation of the plant as a whole when in flower. We'll see what another year of growth and another flowering season does for the plant.

Another species that tends to bloom later in the season for me is P. forrestii, seen above. This species has, for two years now, been the easiest species to use as a seed pod parent. So, if you want to try your hand a hybridizing...start with this species! So far, only two attempts to use it as a seedpod parent have failed. It has worked with species that would not cross with anything else. It's a prolific little species! It's positive qualities for hybridizing are it's neat, compact, perfectly symmetrical leaf habit. It forms a perfect, round, flat rosette. It is also very floriferous, over a long season, and flowers at a young age...all good traits for hybridizing. It's primary negative trait is the long, weak, wiry peduncles. They tend to get long and often form a tangled mess when the plant is in heavy flower. It has been recessive for the flower shape and the yellow blotch on the lower petals...neither of these qualities have shown up in a single seedling! It is dominant for the leaf shape, and the perfect symmetry of the rosette. Thankfully, those long, weak peduncles are about 50/50 in the progeny.

Finally, I thought I would throw in a couple of photos the "other" gesneriads! I actually DO grow gesneriads other than Petrocosmea! I have quite a large collection of other species from various other genera within the family. A couple of nice, uncommon species are in flower now.

Columnea raymondii is showing it's very first open flowers for me. This species is fairly new to my collection. I have always been a fan of the upright Columneas. This one came into my collection as a small cutting last July. It has been growing nicely on the windowsill of the upstairs sunroom, where it gets both eastern and southern exposure. I wish you could see these flowers! They are dramatic, striking, and very large...at least they seem large to me. The flower above is about four inches from base to tip. The petals are a deep, glossy bright maroon/red color with a very heavy substance. The outside of the petals and the tube are greenish yellow. The flowers are underneath the large green red-veined leaves. If you can find this one, you MUST try it!

And last, but certainly not least....a coveted plant for me. I've been trying to find a source for the species Smithiantha aurantiaca for more than ten years...with no luck. When I mentioned this to a friend last spring, she promised to bring a plant to me at the Gesneriad Society Convention in the past July. The first thing I did was to remove a leaf and put it down to propagate. From that leaf I got three more plants. Now, I had insurance! The original plant went into a four inch pot under the lights on the light bench, and was wicked into a reservior of dilute fertilizer water and never allowed to dry out. It grew quickly into a large plant with bronze leaves covered in rusty red hairs. A couple of months ago, the first buds began to appear on a tall, upright central spike. The coloring of the flowers is nearly impossible to capture, but it is intense. This plant is the first thing my eye goes to everytime I enter the room. The blooms seem to be illuminated from within...a bright, cheerful orange color with red spots inside the throat. I'm so happy to have this rare beauty in my collection. I've been attempting to self pollinate the flower, with no success so far...perhaps that explains it's rarity. I'm hoping that it produces lots of scaly rhizomes, but as I said, I am also having good luck propagating it from leaf cuttings. Again, a must have if you ever have the chance to grow it.

So, even with the cold, crystalline, wintery world outside, my home is bright, colorful and filled with it's own versions of the "wonders of winter". I hope that yours is too!

Good growing!!!!!

A New Year and New Discoveries

First, I have to say Thank You! to all of those who have read my blog this year! I cannot express how much I appreciate the comments I've received about it from many of you. It was a bit of a self-indulgence on my part, but I hoped that it would find an audience among others who loved Petrocosmea as I do, and that it might be helpful for those who are learning about them and wish to know them and grow them better...as I do. Today, after only four months the blog has had over 900 visitors from 34 countries. I am amazed!! It has been a lot of fun to put together and I will forever be appreciative to all of you for reading it. I hope that 2010 is a wonderful year for all of you!

The new year is bringing still more new discoveries for me about Petrocosmea. First, the one species which I have found the greatest challenge to flower, finally is beginning to flower! What a great way to start a new year and a new chapter of exploring the wonders of the genus Petrocosmea! Petrocosmea sp. 'Yumebutai' came into my collection as a gift from a great friend and expert Petrocosmea grower, Paul Kroll of East Aurora, NY. This plant was first grown by a grower for the Yumebutai Nursery in Japan and was given to an accomplished gesneriad grower, Mr. Toshijiro Okuto. Mr. Okuto then gave the leaves to growers here in the USA and one of them was Paul. The plant appears as a large form of one of the Petrocosmea rosettifolia group, and initial DNA studies are showing that it is a close relative to that group. Leaves are quite thick and have a heavy substance. They are deep forrest green, with a lighter center. The hair on the leaves is bristle-like and stiff, giving the leaves a very rough texture. The leaves, for me, have not gloss to them, the have a dull appearance. Leaves tend to cup downward.

As I said, it has been a reluctant bloomer. Blooms are quite unique....the resemble those of the rosettifolias, but have only four petals as opposed to the usual five. Flowers are purple, with a creamy white throat. The two upper petals form the typical short hood of members of the Section - Anisochilus. Peduncles are purple, with up to five buds each. It is forming lots of buds, so it appears it will be floriferous. Mr. Okuto's photo of a plant in bloom does show a heavily-flowered plant, however, I cannot see the flowers well enough to determine petal count. I have not used it in hybridizing.....YET!


Petrocosmea sp. 'Yumebutai' finally flowers. Bud and bloom count appears to be high. Flowers have only four petals, making them appear elongated.





Another surprise came this morning, very early, as I went down to the plant room in my basement to check on the Pets. I have been growing two plants of P. minor veined leaf form under humidity domes, in preparation for using them for hybridizing. This morning, as I lifted the dome from the tray, a spicy floral fragrance wafted up from the tray! WHAT? A fragrant Petrocosmea?!? Sure enough, several more "sniffs" of the flowers confirmed that they were indeed quite fragrant. I then began to smell other Petrocosmea in bloom. I also detected a similar, although fainter fragrance on P. sericea. A seedling from a cross between P. sericea x P. minor veined leaf form also has a mild fragrance. Admittedly, I have never checked for fragrance on the flowers of Petrocosmea, so had not noted it before. I will be checking more Pet flowers in the future. If you have these species in flower now, you must check them for fragrance. I suspect that the fragrance was intensified by the humidity dome covering the tray, but I could still detect it later in the day after the tray had been uncovered for a while. A new discovery!

Petrocosmea minor veined leaf form....the flowers of this species have a spicy floral fragrance...at least to my nose. If you have this species...give it a sniff!

Last evening, as I was examining some dissected Petrocosmea flowers under a microscope, I noted that the flowers of P. rosettifolia #3 had four stamens. Most Petrocosmea flowers have two stamens and two staminodes...or no staminodes. This species clearly had four. I checked the flowers of P. rosettifolia #1 and #4 and they two had three or four anthers each. I then went back to double check flowers of several other species...begoniifolia, flaccida, duclouxii, minor, sericea...all of these species have two stamens. What does this mean? I don't know. But it found it interesting. The stamens of rosettifolia constrict to form a "beak" as the anthers are all attached to each other. This is a trait of the species in Section - Anisochilus.

I have sketched the flattened flower of P. rosettifolia #3 below to show the arrangement of the four anthers...pardon my rather crude artistic skills.

A quick sketch of the flowers of P. rosettifolia #3 shows the four stamens encircling the base of the ovary and pistil. The filaments on this species are often crooked with an "elbow" at the midpoint of the filament. The filaments of most other Petrocosmea species are straight.


Last, I would like to honor and pay tribute to a dear friend to all who love gesneriads.....Frances Batcheller. Sadly, in November , 2009, we lost Frances at the age of 96. I was honored to have met and become friends with Frances in 2000 when I attended my first Gesneriad Society (then the AGGS) convention in Tampa, Florida. I had read articles by Frances Batcheller for years. She was a self-taught botanist, and form many years, was THE expert on them. Frances was also an active and accomplished hybridizer of gesneriads and established the judging program for the Gesneriad Society. She was the first Judges Chairman of the Society and many judges remember judging with Frances and learning from her. I was so excited to finally get to meet Frances face to face. We became friends and exchanged letters by mail for several years after that. She always treated me as if she'd known me for years.

Frances Batcheller, in earlier years.

Touring the showroom of the 2000 AGGS convention with Frances Batcheller. I tried to absorb everything Frances said...when Frances spoke, everyone listened!!!!

While at my first Gesneriad Society convention, I won the coveted "Tour of the Showroom with Frances Batcheller" ....an traditional item in the live auction. I wasn't going to pass up the opportunity to "learn from the Master". I still recall trying to absorb every word Frances said about every plant she discussed as we toured the showroom. Frances had a knack for summing up the key points about any exhibit in the gesneriad show with a few, well-chosen words. She had a great sense of humor and was such a wealth of knowledge about every plant. The thing I admired about Frances was that on the rare occasion when she encountered a gesneriad that she did not know, she would turn and immediately admit that it was a new plant to her and she would begin to ask questions about it from anyone who she thought might know the plant. She was always eager to learn more about gesneriads. She always said that a good judge should not fault the exhibitor for the judge's ignorance about a plant.

As Frances' health began to fail in the last few years, a convention never felt the same without her. Frances taught me that I should always strive to learn everything I could about the gesneriads I love. I think of her often as I work with and study my gesneriads. Rest in Peace, Frances.