I am collecting pollen from ist year roses, some are very sparce with pollen so I am collecting and storing.
What suggested timing is required in an air temp. of 70deg.F for.
1 Air drying at room temp.
2 Drying under lamp at 80-90 deg
3 Initial drying until refrigeration is required
4 Refrigeration until freezing is needed
I have tried all methods of drying and storage and want to develop a plan for storage methods. I don’t want to lose fertility by taking steps either too early or late so suggested plans would be appreciated.
Russ.
Drying time is influenced by humidity. Sometimes a day is enough and sometimes more is needed. I like to use film canisters with snap tops. Sometimes I seal air dried anthers and shake them allowing pollen to adhere to the sides and shake out the anthers, sometimes not. I think that if the anthers are not fully dry freezing them can be a problem. Anyway, I then go straight to the freezer. In a study that I did (coming out in that Acta Hort from the International Symposium on Rose Research and Cultivation) with pollen viability at different temperatures and durations, it was clear that under refrigeration viability goes down fast. So, I suggest to just go to the freezer to help maintain viability. Allow the canister to come to room temperature before opening it so you don’t get condensation with the pollen and you are then ready to pollinate.
I question the effect of heat lamps on pollen viability. However, I haven’t read any rose related studies looking at drying at room temperature versus 80-90F.
Sincerely,
David
Thank you David
I have tried many ways to collect and store but from what you say I have been too late getting to freezing(about a week) so I think I will chuck the lot and start again.
I have 1 variety that I can’t replace so I’ll keep that (fortunately it was a rustled variety so it was all collected together and was frozen at 3-4 days) The rest was collected over 3-4 days and with drying and combining suddenly it was a week old before I thought about freezing
This time I will dry for 48hrs then go straight to the freezer.
If I dry then freeze each collection separately will I be able to be able to simply add the thawed pollen to still frozen sample or should both be thawed to combine? Any other suggestions ??
Russ.
Hi Russ, If you have the freezer room, it may be nice just to put the new collection in a new container. If you go to film processing places they often have many empty containers they will be glad to donate. When the time comes you can unthaw the sample and pollinate and use the whole container and throw that one away. Randy Hughes and others use nice snap top containers they get from art craft stores. I like the film canisters because they are free and plentiful for me and I don’t feel so bad throwing them out afterwards.
Sincerely,
David
I suggest drug pill containers. If you are not in the position (envy) of having a sufficient supply from your own family perscriptions, perhaps your parents or elderly neighbors will agree to save them for you (especially if you share some cut roses with them from time to time).
May I also ask, approximately how long can pollen be stored for at room temperatures of say 70F - 95F and relative humidities of 60%-80%, and still be ok for use?
George,
Those conditions significantly shorten the life of pollen. I would not use pollen stored under such conditions once it was more than about 3 days old, maybe 4. If temps don’t much exceed 75F, then maybe it will last a week. Ideally you want to use pollen within 48 hours of removal from the donor. If you don’t expect to use it for a week or more, then dry it and freeze it.
Paul
Thanks Paul, will do…I’ll stick to 48 hrs, as temps are sometimes going over 100F now.
:0)
I have not tried freezing pollen, but may try it someday. It seems that there are always matches available to keep me busy using available pollens with available seed parents, however, I do understand that certain desired crosses may necessitate storing pollen for a longer period than would be possible without freezing it.
I do not use pollen that is more than 2 days old from harvesting. To extend the number of days that I have viable pollen, I have used refrigeration. That has worked very well for me. I use this method in circumstances where I have blooms of a desirable pollen parent that are blooming within about 1 week before the desirable seed parent will be blooming. I will pick the pollen parent blooms 1-2 days before they would normally open and place the blooms with their peduncle ends wrapped in a moist paper towel in a ziplock bag and into the refrigerator. These blooms can be taken from the refrigerator for up to 1 week afterwards and pollen harvested from them for drying in the usual manner as with fresh blooms.
Jim Sproul
Temperature and moisture are two major factors in the deterioration of pollen. Over the years, I’ve had much better results with newly harvested pollen than with pollen that has been sitting for a long time either in the freezer or in the refrigerator or on a shelf. Probably everyone has had similar experiences. Pollen kept dry in a cold freezer for a year will usually work, but not nearly as well as that which you got fresh the day before.
Sure, pollens from some kinds of plants (grasses, for instance) may last with some viability for hundreds or thousands of years in some circumstances, but rose pollen is not nearly that durable. Under normal conditions (not too hot, and not really humid) you might get a fair percentage of seed set with pollen that is a week or two old–but if you can have fresh pollen, use it. And if the pollen comes in the mail, use that–whatever its age–and hope for the best.
We don’t have to guess about these things: research provides fairly conclusive evidence. Take a look at the abstracts of these two articles–
http://www.springerlink.com/content/k74671kn00308387/
Jim, I am definitley going to make good use of your idea…it will save me all the worry about timing flowers to eachother, which for me is an issue that requires me to have to do a lot of driving between where I live and my mother’s place where the roses live (where I live in the city, I have a cement back yard unfortunately…LOL)… BRILLIANT!
I would love some advice on the best way to freeze pollen (ie. what steps are required).
I collected pollen from ‘Hot Cocoa’ and ‘Ebb Tide’ yesterday about 16 hours ago, and then put the anthers in a baby food jar (lid off). I have these two jars sitting on a shelf indoors.
So now what do I do?
Do I shake the bottles and get the pollen on the sides of the jar, then tip out the anthers and freeze the pollen granules with the jar lid on?
So… I just made my first attempts at storing pollen. I made little paper cups out of notebook paper. Collected the anthers in the cups. Let them dry at room temperature for 24 hours with some air circulation (they seemed all nice and crispy). Wadded the ends of the cups up to where the pollen was at the end in a ball. Wrapped Saran wrap around each one. Wrote the variety of each one on the saran wrap and put them all in a plastic pill bottle and in a deep freezer. Two questions. First, is a deep freezer too cold to store pollen? Second, will it retain viability until spring (four or five months away)?
-thanks!
Jon,
Actually the colder the freezer is the longer the pollen will stay viable. David Z published a paper on this topic a number of years ago. Pollen will stay viable at 0 degrees F (what most freezers are set at) for up to a year. I have stored pollen in the freezer and used it the next season for a number of years now. It probably isn’t as viable as fresh pollen so you probably should use more of it at a time. I have probably 20 or 25 film containers with pollen in them in the freezer right now. You want to make sure the pollen has dried well and that the containers are airtight.