Rose Hybridizers Association Forum

This is amazing Don!! Wow, this could be super useful in many slow to mature perennial crops. I've sat in presentations where people used transgenic apples to get early flowering and then they just select the offspring that don't have the transgene to identify possible plants that could be commercia...

Hi Duane!

I have used 2 year old pollen successfully that has been frozen. I don't know how much viability goes down for sure, but I was able to get successful seed set this past year from pollen collected 2018.

Your seedling is gorgeous!! I love the glossy dark leaves and full petaled blooms. Is it a miniature? I've gotten seedlings with some similar characteristics out of 'Rise 'N Shine'. Minis can be great for helping produce a nicely branched plant (as well as polyanthas).

I'm excited to hopefully find them this summer and try them. They look really nice. It is great Monrovia has the option to buy them on their website and we can have them dropped off at a local garden center that buys in Monrovia products with their trucks going that direction anyways. It seems reall...

Your hybrid looks beautiful Joan! Those roots on the cuttings look really nice and robust too!!

I wish I understood the interactions between the genes in the flowering pathway better... I get confused easily and have to review the basics again when I try to keep straight in my mind the role of RoKSN (aka TFL1), FD, Leafy, etc. Anyways, in 2017 at the rose meetings in Anger Dr. Fabrice Foucher ...

Hi Larry,

If I remember right the ones I sent trace back to seed sent from Boerner Botanical Gardens in the Milwaukee area in the 1960's or early 1970's, but I couldn't find information on where they obtained their plants.

Hi Sarah! The American Rose Trials for Sustainability (trustedroses.org) uses this system too for regional awards. The combination of temperature and precipitation patterns seems to make it more useful than just the minimum coldest temperature like for the USDA Cold Hardiness zones https://www.ameri...

Dimitre and Maher do such great work and it is nice they are mentoring others in these techniques. I'm grateful they continue to do virus discovery work with roses, especially when it is generally easier for them to secure money to characterize new viruses in other crops.

I doubt it too.... The resistance is dominant. Brite Eyes has only one copy of that dominant allele across its 4 sets of chromosomes and just a portion of its seedlings inherit it. There is a race of black spot that can overcome Brite Eyes, but most all the races in our collection don't. If your BE ...

That's a great question... I assume they mean that through many years and propagation cycles plants begin to show "drift" / decline in terms of performance, especially if careful attention isn't given to propagating from just the most representative plants. For part of my Ph.D. I studied performance...

Hi Philip, I ordered the liquid form of Bti from a Florida pond supply company (123Ponds; I think it was a 6 or 8 ounce bottle, I have to check- it was about $20 I think). Their main customers are using it for mosquito control in ponds and that is what is on the label when it came, but the website s...

Hi Duane!! I'm excited for you to follow these. Hopefully you can just put them all into larger pots and prune them as needed to keep them all in their space allotted until spring. It would be a shame if they vary for health and other traits and you miss the opportunity to discover those things at t...

That is wonderful rikuhelin1!! I'm so glad they are taking. Thank you so much again Stefan!! I got Bacillus thuringiensis subsp./var. israelensis and it is working. After the first application it really knocked the fungus gnats down and a couple weeks after now I mixed some more and treated again. I...

Hmmmm It looks like the rose I've seen in the past at the MN Landscape Arboretum labeled 'Kakwa', a spin hybrid. The wide hypanthium under the sepals suggests Spin hybrid to me. At the MNLA 'Kakwa' got about chest high and 6-8' wide and died back somewhat each winter.

I added a link to a paper by Dr. Kermani et al., 2009 characterizing various species of fungi causing rust in roses. This seems like a pretty diverse group of pathogens for having such a variation of species causing similar symptoms and growers calling it all by the same disease name. http://www.glo...

Wow, thank you sooo much Stefan for pointing out Bacillus thuringiensis and this strain labeled for fungus gnats. I'm super excited to get some and think it'll be less expensive and have a longer residual than hydrogen peroxide. It becomes difficult for me with lots of seedling trays of small cells ...

One thing I've tried last year that has really helped with fungus gnats with seedlings is hydrogen peroxide. I've mixed it about 1 part 3% from pharmacy to a few parts water. The media bubbles and kills the larvae and hasn't seemed to impact roots of rose seedlings. It takes a few applications since...

I notice that too.... I wonder too if I have them too wet. I suspect in some instances the blackening may be due to one of the root rot organisms getting in and disrupting the vascular system and connection between the top of the cutting and roots. Sometimes when I have cuttings I'm potting up and t...

This is just a guess, but 'David Thompson' from Svejda. It was popular "a long time ago" in relative terms (~20 years ago) and routinely sold for awhile with her other wonderful Explorer roses. I think it is more petite in terms of its leaf size than the other commonly sold double magenta rugosas.