Captan, etc, what & where?

Hello, I’m a new member, and this is my first post! For two years I “dabbled” in hybridizing, and never had a single seed germinate! Not one. This year, I’m done “dabbling”. I’ve studied hard, and have successfully made many crosses. I’ve also collected many OP hips, so I have high hopes that this will be the year I’ll feel the joy of seeing my first seedling sprout.

My question is about the element I should use to prevent disease and damp off when stratifying. I’ve read about “Captan”, but my local nurseries have never heard of it. The last two years I used peroxide diluted in water, and I wonder if this killed my seeds. Please tell me: What should I use and WHERE DO I BUY IT?? (I live in Southern California).

And I’d like to thank you all – I’ve learned so much from you!

Hi Wendy,

I follow Paul Barden’s advice and use nothing. See:

Link: www.rosehybridizers.org/forum/message.php?topid=6478#6490

Hi Don,

Thank you for the wise advice. I would prefer to use nothing. If Mother Nature didn’t need captan…

Wendy:

I read your question about Captan. I grow roses but have

not grown any from seed so cannot answer your question about using Captan during seed stratification.

Captan is a very old fungicide and was used a lot in the

orchard industry for controlling apple scab. I see the webpage for RosesInc.Tulsa offers

Captan 50WP for sale. You may try them out for availability as they ship their products by Fed EX I believe. I just ordered from them for the first time a few

days ago and saw Captan listed on their website.

Wendy,

Captan does work against some damping off fungi, but I have had better luck with Banrot or Benomyl.

The MOST important thing, however, is the growing medium. The seed starting mixes and potting soils you find at the stores hold way too much water. I now use one part seed starting mix with one part perlite and one part vermiculite. Cover the seeds with pure perlite and water from the bottom.

I no longer use Captan as it has been shown to have some carcinogenic properties. I follow Ralph Moore’s technique of simply pressing the seeds into the surface of the soil mixture and then covering the seeds with 1/4" of fine Perlite. This eliminates 99% of damping off without chemical intervention!

Paul

Well, thank you so much for the advice!

I have planted these seeds in little tupperware cups with lids, thinking this is a clever solution to keep them damp in the fridge. Perhaps I had a blonde moment, not considering the lack of drainage? Sounds like I need to replant into growing trays with some perlite. Sigh. So much to learn!

Hi Wendy,

Yes, if you are planting them for germination and growing, you will want good ventilation - both above and below. I do stratify in ziplock bags, but plant seedlings exactly as Paul describes. I too have abandoned Captan, although I do a light drench in the greenhouse of Subdue (I doubt that it helps much, but have continued because I haven’t had much dampoff).

When I planted in trays, watering from the bottom with Perlite on top as described by Shane worked very well.

I wish you great success this year - you will be hooked!

Jim Sproul

Wendy, there’s no great magic in germinating seeds and many methods work. I germinate the seeds in plastic baggies and then plant the germinating seed in store-bought bagged seed-starting soil. The method I use is on my web page and I do use peroxide. Perhaps you’re not keeping the seeds on the bush long enough? Or maybe you’re using mother plants that make hard to germinate seeds?

Anyway, keep trying! You’ll figure out what you might be doing wrong.

Link: www.abrigon.com/Rose%20Hybridizing%20Presentation%20Final_files/frame.htm

Well, Judith, you’re absolutely right that ONE of my problems has been using parents that simply didn’t want to reproduce! I laugh now, but imagine my surprise when I read on these very pages all about the pretty pink rose that was ALWAYS in bloom in my California garden - that one I thought had such awesome characteristics to breed for - that rose I had tried crossing more than any other - that rose called “Belinda’s Dream”…

(Ahem. I hear you all chucking out there…)

So I’m MUCH wiser on that count this year. I did my homework.

As for the age of the hips - well, that’s an interesting topic to me. I have no idea how old they were when harvested the last two years, but I’m keeping good records this year so I’ll know what worked. I’m still not sure when a hip is ripe and ready to go. Every bush is different, yes? Of those I’ve harvested so far this year, they’ve ranged from varying colors of orange to being completely shriveled. I’ve had squirrel issues, and some broke off or I grabbed them in a panic before they were fully ripe because they were getting “nibbled”. I’m trying to ripen them in some damp soil in the window, and it seems to be working! And some, believe it or not, are still ripening on the bush. (I crossed some late. It doesn’t freeze here in Burbank, so…) Those are now protected from the squirrels in sheer cloth. These are some of my most important crosses, so I’m letting them stay on the bush until… I guess until the stem turns brown, right?

Anyway, thanks to all for the tips and the pep talks! It really helps!

I never wait spacifically until the stem turns brown. I harvest either 1) when the hip has turned orange and has been on the bush at least 100 days or 2) when the hip has been on at least 4 months and it kinda looks a sickly yellow/green and the sepals are dried and/or the stem is starting to turn color or 3) if the hip has been on for 5 or 6 months even though it’s still green and the sepals fresh. Each rose variety is different.

One big surprise I had this year was a cross I made on a supposedly sterile Frivolous Pink x Paul Ecke, Jr. I let the hip stay on the bush for 6 months, removed the seeds immediately, soaked them in bromelain for 24 hours, then in H2O2 for 24 hours, put them in a plastic baggie with a paper towel moistened with H2O2, and 2 DAYS LATER I got my first germination before cold stratifying.

Seeds have their own mind!