The great outdoors: pollen viability & hip maturity

A few questions here

Dee, I suggest freezing it. I presented research on pollen viability over time stored at different temperatures at the 4th International Symposium on Rose Research and Cultivation Sept 2005. The Acta Horticulturae volume where the whole manuscript will be published should be out soon. I found that pollen in the fridge went downhill fast, but the freezer preserved pollen much better. I stored pollen for a year and periodically removed samples and looked at in vitro germination rates and pollen tube lengths. I also made pollinations with variously stored pollen too and report seed number per hip. This research is highlighted in the Summer 2006 RHA newsletter.

I just take flowers with their petals removed and the neck still on the flower and put them in film canisters upside down to dry for a day or so (usually one per canister). Next, I hold onto the neck of the drying flower and shake the stem around inside the container and then throw the stem away. Pollen is released and accumulates in the canister. Next, I snap on the lid, labeled it if I haven’t done so already, and stick it in the freezer. When you use the pollen, let the cansister come to room temp before you take the lid off. Otherwise there will probably be condensation inside the cold container wetting your pollen.

Good Luck,

David

Dee, I do many of my crosses outside. Depending on your climate, a greenhouse is not necessary.

Jim Sproul

I’ve done ALL of my crosses outdoors – since I don’t have a greenhouse. I would certainly try some crosses in a greenhouse, if I had one, because I’ve read that some crosses have only been successful done that way.

And I agree with David’s suggestion to freeze your pollen for later crosses. That’s worked well for me too.

David - I like the idea of picking the whole flower for pollen collection. It must save a lot of time. Great suggestions. Thanks.

Well that is good news; thank you :slight_smile:

Dee, I have not had any luck with pollinations up here that were made much past the end of June. In the first year of serious crossing most of my crosses were made in the first half of July and the hips never fully ripened before I had to save them from a killing frost. I think that the general rule is to have mature seeds it takes about 3 months after pollination. There is some variation to this give or take a few weeks depending on the rose. This past year my cut off date for pollinations was June 29th for females that were planted in the ground and July 18th for females that were potted minis. I moved the minis into the house to protect them from frost in the fall. So far the seedlings that are up this year came from the early June crosses and the early July crosses.

Liz

O.K. Liz, now I’m concerned; I forsee problems with what you’ve just said. Most of my Austins, and all HT’s start to flush the last week of June, are in full flush the 1st & 2nd weeks of July, then start to fade in the latter half.

Since my roses grow in an open area out in the country, the temps are a little cooler than most in-town or neighborhood locations. So they flush a week or two ahead of everyone else’s. For the last three years I haven’t been able to enter my HT’s and Austins in the Huronia Rose Society’s June exhibit because it’s always scheduled to suit THEIR blooming times (mid-late June), when mine are just starting to flower. By the time mine are in perfect flush, theirs are always blown, lol! So this time they’ve pushed the show dates a little foreward, however marginal that is.