Tuesday, May 26, 2020

New Hulthemia Seed Parent Selection and Cross

This 2018 seedling sets hips marvelously well.  Code named "V6", I think that every bloom could produce a hip if I let it, and being a very floriferous seedling, this one could produce a ton of hips.  The blooms when they first open are yellow with a very dark central blotch.  As they age, the yellow becomes a darker apricot color with pink tones.



I decided to test it's germination rate and was very pleased to find that germination was sufficient to bring it into the breeding program as a new seed parent.  From 10 hips, there were 181 seeds that were extracted (see seed parent listed below, "V6 large blotch").  Of these, 41 germinated (22.65%).  

The germination rate may seem a bit lower than ideal, but looking at the other statistics, you get a different picture.  On average, I get about 9 seeds per hip overall in my breeding program.  If the "V6" hips contained an average number of seeds, I would have planted about 90 seeds (9 seeds/hip with 10 hips harvested).  If there were 41 seedlings coming from 90 seeds, the germination rate would be 45.56% which is a very respectable germination rate.  In the end, when selecting for a good seed parent, I consider the number of seedlings that I get per cross, since making the crosses in the first place is one of the more labor intensive activities to this rose breeding hobby.  Remember too that this seedling sets hips very easily, while some other seed parents abort many of their hips.  I am most interested in being as efficient as possible with the crosses that I make.....

So, what to cross with this new seed parent??

Although I am using a handful of pollen parents in crosses with "V6", my most anticipated cross is with 'Ringo', a newly introduced rose to the U.S. ‘Ringo’ (AKA ‘Eye of the Tiger’) is a single petal Hulthemia bred by Chris Warner, and is new to me this year. Because of it’s excellent disease resistance, ‘Ringo’ has won several international awards. It is the first new Hulthemia from another breeder that I have added to my breeding program in many years. I am interested in it's cleanliness (immediately below is a photo of 'Ringo', followed by photos of "V6" blooms that have been prepared for pollination).

My favorite number of petals for a Hulthemia to be most attractive, while able to show off it's blotch, is somewhere between 10-15 petals.

With all of this in mind, I set up the cross between "V6" and 'Ringo' in hopes of producing very clean, floriferous Hulthemia seedlings with heat stable blotches, having good coloring and with 10-15 petals.  From the many crosses that I've made, all that I need is just one.... 😀