Summer's Treasures

Summer is not usually a big season for blooming Petrocosmeas, with most species being autumn and winter bloomers.  An advantage to having a larger and more diverse collection of Petrocosmea hybrids and species is that there are some which do flower in the summer.  For me, P. barbata, P. nervosa and P. parryorum have become reliable summer bloomers.  Hybrids incorporating these species also show a tendency to flower during the longer and warmer days of summer. 

A few years ago, I was excited to add two new cultivars selected from a remake of the same cross that produced the old hybrid P. 'Momo'.  This time, Mr. Nakayama, who incidentally produced 'Momo', chose two cultivars that exhibited new and desirable qualities.  P. 'Asa Blue' was selected for it's tendency to produce tremendous quantities of large blue flowers.  Now, after growing this hybrid for several years, I can say that it clearly takes a few years for it to reach it's prime.  My original plant, pictured below, has finally shown it's potential for me.  The plant shown is currently putting on a spectacular show on the north facing window sill of my bedroom.  What a joy it has been to awaken to this joyous sight each morning for the past two weeks.  It shows no sign of fading and there are still lots of buds coming along.  Today, I counted 56  open flowers.  The plant has been growing in a five inch pan pot for the past four years, and has not been repotted.  I have grown it under lights, until two weeks ago, when I brought it to the windowsill so that I could enjoy the show more readily.  I advocate keeping Pets in the same pot for several years, and not over feeding.  I also believe that allowing the plants to get dry between waterings encourages more flowers.  Overfeeding and keeping plants constantly moist, at least for me, produces large leafy plants, but few flowers. 

P. 'Asa Blue' (above) in flower this morning on my north facing bedroom windowsill. 

P.' Asa Blue' also has been successful as a parent in one cross for me.  The photo below shows one of it's progeny...P. 'Keystone's Brilliant' (P. 'Asa Blue' x begoniifolia).  This cultivar was selected for the bicolored flowers with lots of white in the throat.  A nice yellow center also adds to the brilliance of these flowers.  My one plant of this hybrid is just now coming into flower.  It has always flowered in summer for me, making it another hybrid with potential as an "off season" bloomer among this genus which mostly flowers in the winter. 

                                              P. 'Keystone's Brilliant' just coming into flower.

As more and more hybrids are produced, hopefully, we will one day have Petrocosmeas in flower all year long.  For now, these few summer-blooming Pets are treasures in the long, hot days of summer. 

Hello friends!     It's been a while since I've posted to the blog.  I have not been stagnant, however.  Thanks to all of those who have written.  I've gotten lots of emails on Petrocosmea-related topics, and many have asked about various aspects of Petrocosmea culture.  I've decided to use those questions as a guide for future posts, since those of you who have written have often mentioned that you know of others who are having similar questions.  The support for this blog is overwhelming.  I never envisioned it being as popular as it has become.  The level of interest in Pets has grown over the last few years and continues to grow from what you are telling me.  So, I decided to kick of the new posts with this one which is basically just an update on what my Pets and I have been up to.  

First, something fun!   Below is a photo of my newest seedling to flower.  I am very excited that it is flowering now, in summer, a time when most Pets are in active growth here in southwestern Pennsylvania, where for a couple of weeks now we've been having a record-setting heatwave and drought.   Why does that excite me?  Well as a hybridizer, one of my goals is to extend the blooming season for the normally strongly seasonal winter flowering genus.  Most Pets for me flower between October and March.  Having a seedling flower now gives me hope that it might provide a plant that will flower both in summer and winter, thereby extending the season of the Pets for the home grower and for summer shows.  The second exciting thing about my new baby is that the flower is white!  Bright, sparkling, purest white with a sunny yellow center!   The cross is P. forrestii x begoniifolia.  P. begoniifolia often flowers in summer, so I'm sure that is where the bloom time for this seedling comes from.  It also is a white seedling of a cross where one parent is lavendar (P. forresttii), so that means that P. begoniifolia may be dominate for color over P. forrestii.  This is only my second hybrid seedling that has ever had white flowers.... the other P. 'Keystone's Bantam' was a white seedling from among nearly forty siblings all of which were purple or lavendar.  It will be fun to see how this current seedlings' siblings flower. 

The first seedling to flower from P. forrestii x begoniifolia is pure white!!  No sign of the lavendar flowers which it's maternal parent has.  Will the other seedlings in the cross also be white?  Time will tell............

I'm growing out 13 seedlings from this cross....all that were produced.  Few seeds were produced, and only these 13 germinated.  The seedlings germinated last January and are now six months old.  Only one has flowered.  None of the other are showing buds.  Foliage is more like P. forrestii, but with the rounder shape and deep bubbly veining of P. begoniifolia.  I had hoped for some of the burgundy purple undersides to the leaves from P. begoniifolia, but so far, none are showing that characteristic.  I would love to self and sib cross some of these to see what happens to flower color and foliage in the F2, but often Pet hybrids have been reluctant to produce pollen for me.  Of all my crosses, this is the one I would most like to sib cross to get an F2 generation. 

The tray of P. forrestii x begoniifolia seedlings. The dark green foliage makes the white flowers of the first seedling to flower really stand out!   I will soon have to seperate them and give them more room.  They are going to be more like the P. begoniifolia as far as plant size goes, it appears.  Some are producing lots of offsets (which I detest in hybrid seedlings).  I often select against offset production in seedlings...so once they flower, unless the flowers are truly spectacular, those will likely go into the garbage bin. 

So, that's the most exciting thing in the Pet Cave right now.  I look forward to getting back to the blog and "talking Petrocosmeas" with you again.  ~ Tim

Petrocosmeas (and this blog!!!) in the News!!

Finally!!! Petrocosmeas are in the news and getting the attention we all knew they deserved! I was delighted by an article in the RHS publication "The Plantsman" back in September that announced a new name for one of our most popular Pet species...the former Petrocosmea rosettifolia. The new, and proper name for this plant is Petrocosmea cryptica as described and published by Julian Shaw of the RHS. I am attaching a link to the article here:
www.rhs.org.uk/Plants/RHS-Publications/Journals/The-Plantsman/2011-Issues/September/Petrocosmea



Petrocosmea cryptica '#3' (formerly known as P. rosettifolia #3) shown above. There are several variants or clones of this species in cultivation. The one above has attractive leaf markings and large, pure white flowers with yellow throats.


Mr. Shaw finally did some of the much-needed taxonomic work on one of the more popular species in cultivation now for around ten years. In his article, Mr. Shaw mentions the fact that this species has been improperly labeled P. rosettifolia, and has also been distributed under various other names such as 'G25KC00' which I've discussed here in previous posts. In my collection, I've accumulated at least nine plants which I believe are simply different clones, likely from different collections, of this species. DNA analysis which we did with Niagara University, has shown that these various clones are all very closely related genetically, so close, in fact, that we believe they are all the same species. It is common from a species to contain individuals with quite different characteristics.

Pictured above is a plant in my collection which I call P. cryptica '#5 '(formerly labeled P. rosettifolia #5). This form has less distinct yellow veining in the leaves and lavendar flowers.

Pictured above is P. cryptica '#4' (formerly labeled P. rosettifolia '#4'). This form has white flowers and a distinct and vibrant yellow veining to the leaves. The flower form on this clone, to me, is less attractive than that of #3, but it tends to flower more heavily, and later than '#3'.

The photo above shows the variability in the foliage of P. cryptica clones in cultivation. This photo shows my plants of P. cryptica '#4' at the top and P. cryptica '#1' at the bottom. Two forms #1 and #2 both have leaves that are nearly totally green and more rounded in shape with smooth margins. Other clones show the distinct yellow veining and toothed leaf margins. Clones #1 and #2 also grow much more compact and have flowers in light lavendar to pink shades. DNA analysis, though, does show them to be the same species as the showier forms.

Mr. Shaw's article has lots of good information in it. And, it mentions this blog and three of my hybrids using P. cryptica - P. 'Rosemary Platz', P. 'Keystone's Bantam', and P. 'Keystone's Harvest Moon'. The first two are registered with the Gesneriad Society and show P. rosettifolia as the parent, since that was the name applied to the species at the time.

In the future, I hope to see more taxonomic work done on the many Pet species still being grown and distributed under names that are clearly incorrectly applied. P. minor and it's various forms being one in this group. P. sericea and sp.' HT-2' are also suspect in my opinion.

So, the question I am getting is "Should I change the labels on my plants?". I have changed my labels on the plants which I am reasonably certain fall under this newly published description. If I am in doubt, however, I say what I always say...keep the plant labeled as you acquired it, along with a notation of where and when you acquired it. One day, perhaps we will have the mess with Pet names sorted out. For the time being, though, enjoy growing the plants as they are.

A Sincere "Thank You"

Petrocosmea sericea, in my plant room this morning!

I've missed blogging about my favorite plants। Sometimes, one is blessed with lots of "passions" in life, and priorities must shift. With only twenty-four hours in a day, and only one of me, the time left for plant passions is limited to only enough time for watering and maybe a little fertilizing and repotting. I'm happy to say, though, that at least for the moment, I'm finding a bit more time to not only water and fertilize, but also to stop and smell the Petrocosmeas (see my last post!!).

Most importantly, I must stop to say a most sincere "Thank you" to all of you who have taken the time to write, share photos, seek advice, and tell me of your experiences with Petrocosmea. It means a lot to hear that you have found the posts here on the blog helpful to your enjoyment of Pets. In the time that I have been away from the blog, I have continued, as time permitted, to do some experiments, study both old and new species, and to continue to grow and evaluate new seedlings for future release. I continue to learn so much about these plants every time I work with them. The feeding, watering and fertilizing may have been scarce, but my enthusiasm for the Pets remains. In your letters, you have given me many ideas for future posts, and I will do my best to get to those as soon as I can. Thank you for the suggestions, comments, and questions.

So, this morning, having a rare day off, I arose early and went to the basement to work with the plants. I was welcomed by the plant pictured above...Petrocosmea sericea, giving it's annual show of bloom. The plant pictured is now about ten years old. It was one of my earliest acquisitions as a gift of two leaves from a friend. This senior amoung my collection has been in the same pot for about four years now. It is potted in a 1:1:1 ratio mix of peat, perlite and vermiculite and is in a five inch pan pot. It sits on an acylic matting that is occasionally moistened for humidity. Humidity in my basement never gets below around 50% year round, and is often higher. This summer, as my work schedule has gotten busier, this plant has wilted several times and has only been fertilized maybe twice in the last year. But it is happy. This photo reasserts my advocacy of letting Pets dry out between waterings, and for going light on the fertilizer. One of the most common questions I get is "why won't my Pet bloom?" Often, with some questioning, I hear that the plants are kept constantly moist and fertilized often. It is true that his treatment makes lovely and lush foliage, but I fear it is at the expense of flowers. Pets in nature often grow in rather harsh conditions where they dry out between rains. Prior to taking the photo, I removed 17 spent flowers and there are 68 flowers still on the plant, if I counted them correctly. It makes a lovely sight and you can see the flower potential if given proper culture. SO, this morning, being greeted by this lovely sight, I took the time to stop and smell the Petrocosmeas! (I have three of these P. sericeas in bloom now.) And remember, this species is fragrant.... the scent is great! I hope you have some Pets in bloom to enjoy too~!!

Petrocosmeas with Fragrance

I've posted about this before, but wanted to remind those of you who are growing P. minor or P. sericea, or P. sp. 'HT-2' to sniff the flowers when they bloom for you. This year, in the GS Convention show, Paul Kroll entered a flowering P. minor. This was an unusual entry since P. minor rarely blooms at this time of year. I used this opportunity one morning in the showroom to conduct an informal survey with those who were viewing the show.

I asked ten people to sniff the flowers of the P. minor. Seven of the ten people could detect the fragrance. It was mid-afternoon, and for me, the flowers are most fragrant very early in the morning, but still the fragrance was there. Of those who could smell the fragrance, I asked them to describe it. All said "spicy", four also detected a floral scent along with the spice.... two said it reminded them of carnations. Three people could not detect the scent at all. I find that for many of the gesneriads that have fragrant flowers, there are always a good percentage of people who cannot detect fragrance. Covering or enclosing the blooming Petrocosmea will also help to concentrate the fragrance. I also feel that some clones are more fragrant than others. The veined leaf form of P. minor, the one often labeled P. sp. #5 is the most fragrant.

So, just a reminder to take the opportunity to enjoy yet one more incredible trait of these fabulous gesneriads!! SO take the time to "stop and smell the ....Pets!"

Petrocosmea minor Kinship group

This year, I entered my first Petrocosmea Kinship Collection in the Gesneriad Society Convention show. A Kinship group is an effective way to showcase a parent and its offspring. Dominant characteristics can easily be illustrated with this type of entry, as well as utilizing the entry to introduce new hybrids.

I chose to showcase Petrocosmea minor and four of its hybrid offspring since P. minor has been quite the challenge to hybridize with. It has never performed successfully for me as a seed parent, and has only functioned as a pollen parent in three crosses so far. I must have pollinated a hundred flowers, actually likely more than that. Last year, I think I applied pollen to every P. minor flower that opened, all failures. The crosses that have worked have been P. minor crossed onto P. forresttii, P. sericea, and P. rosettifolia. The cross with P. sericea, which like P. minor has fragrant flowers, also produced fragrant offspring.

Pictured above is my Petrocosmea minor Kinship Collection. Starting with P. minor at the top, and moving clockwise, there is P. 'Paul Kroll', an unnamed seedling of P. rosettifolia x minor, P. 'Keystone's Blue Jay', and P. 'Keystone's Slippery Rock'. I used tan fabric as a unifying drape for the collection since I like the brown tones against the green Pets....

Pictured above is a new hybrid P. 'Keystone's Slippery Rock' which is P. forresttii x minor. This cultivar had lots of flowers and inherited a nice compact rosette from P. forresttii and the shiny round leaves of P. minor. It was my favorite seedling from the cross. Slippery Rock is a city about an hours drive north of my home in Pittsburgh, in western Pennsylvania. The glossiness of the leaves reminded me of a slippery quality, so the name was to honor a great university town in PA.

Pictured above is P. 'Paul Kroll' a sibling from the P. forresttii x minor cross that produced P. 'Keystone's Slippery Rock'. This plant has flatter leaves with more prominent veining, a dark green round leaf with a bluish coloration and a nice combination of glossiness and hairness to the leaves. It was the most floriferous plant from the cross, producing LOTS of flowers. You've heard me mention my friend Paul on here before. Paul is a skilled grower of Pets and has shared lots of new Petrocosmeas with me over the years, so I wanted to honor him with this new hybrid.

The Kinship group got lots of positive comments and received a first place ribbon from the judges. I had lots of requests for leaves of the new hybrids, so I hope they will be enjoyed by other admirers of Pets soon.

Petrocosmeas Go To Convention!!!

Well, the annual international convention of the Gesneriad Society is but a fond memory now, but what a great time we had! Philadelphia was the site for this years convention and the fast-paced week was full of fun, friends, and of course gesneriads! While I do love the plants, I always leave convention reaffirming that the chance to spend a week among friends who also love gesneriads is the best part, and this year was no exception. On the Petrocosmea front, Pets got their fair share of attention. I was overjoyed to see some of my own hybrids being grown and shown by others....a "high" that every hybridizer enjoys.

Petrocosmea 'Keystone's Bantam' won big this year and was selected 'Best Petrocosmea'. The plant was grown and shown by Richard and Nancy Carr of Ohio. An interesting story about this entry was that the classification committee almost didn't let Richard and Nancy show the plant as 'Keystone's Bantam', insisting that it was actually P. rosettifolia. I was asked to come over and help to sort out the confusion, which we did. The Classification Committee were simply unfamiliar with the characteristics of the hybrid, and honestly thought they were helping the exhibitor to correct some mislabeling. The distinction, when out of bloom, is that 'Keystone's Bantam' is significantly smaller in leaf and rosette size and a bit hairier than the species P. rosettifolia. A P. rosettifolia with that much leaf volume to the rosette would have been three times the size of the little plant that the Carr's were attempting to enter. The confusion was quickly cleared and the plant was entered. It did well in the judging too! I was as proud as the Carrs were, I think!

P. 'Keystone's Bantam' also showed up in the Photography classes, and performed well there too! Dale Martens did a very skilled job of photographing her little plant early one morning just as the sun was rising and casting a golden glow upon the little plant. She captured this in the photo and the judges recognized her skill by awarding her a First Place in the class and 'Best Photograph' for the Division. Dale, a dear friend of mine and my hybridizing mentor, kindly gave me the photograph after the show! I was touched by her generosity and the photo now hangs in a prominent place in my living room.

Mary Lou Robbins won a second place award for her needlework interpretation of a photograph from this blog, taken of my hybrid seedling P. forrestii x sericea. Mary Lou wrote some time ago asking for permission to use the photo in a craft entry, and this is the result. I loved it! She even used longer tufts of thread over the calyx lobes to mimic the hairiness of this hybrid. It was a First Place effort in my book Mary Lou!!!

Another friend, Paul Kroll, executed a wonderful design using a Petrocosmea sericea as a focal point in his design. The theme was Punxy Phil, the legendary ground hog from Punxsatauney, PA, who emerges each February 2nd to predict the arrival of spring according to whether or not he sees his shadow. This design required that hairy and fuzzy gesneriads had to be incorporated into the design. I loved this one! The pieces of slate at the base were intended to suggest Phil's shadow.

This photo, taken on the last evening of convention shows some of my dear friends and mentors in my gesneriad adventures. From the top left are Dr. Bill Price, Mary Lou Robbins, Ben Paternoster, myself. Middle row L to R are: Paul Kroll and Arleen Dewell. Front row L to R are: the legendary and beautiful Rosemary Platz, namesake of my first Petrocosmea hybrid, Karyn Cichocki, Dale Martens, and Jill Fischer. We enjoyed a wonderful dinner on our last evening together. Each of these people has taught me something about gesneriads over the years that I have known them. In all things in life, having mentors and friends is most important to success. I have been most fortunate to have lots of both. I wish the same for each of you.........