Hybridizing Daylilies
by Diane Linsley
Part One: Choosing Good Parents
There's no point in going to all the work of
hybridizing daylilies unless the end result is
a nice daylily. So before you get started, you
might want to do some research. Here are
some tips for choosing good parents:
1. Find out which daylilies are being used by successful hybridizers. Their websites and catalogues usually list the parentage of new introductions. You may not want to copy their work, but studying what other people have done can give you ideas. You can also go to Google and type in a daylily you want to breed with the letter x in quotation marks. For example: "Elegant Candy x". Then do a separate search for "x Elegant Candy". This will show you the crosses that people have listed on the internet, first with Elegant Candy as the pod parent, then as the pollen parent. Another good resource is Charlotte Chamitoff's Hybridizer's Corner. I also enjoy visiting Floyd Cove Nursery.
2. Decide on your hybridizing goals. Do you want to breed daylilies with unique eyezones, fancy edges, clear color, high bud count, or all of the above (that would be some daylily!) Make a list of the daylilies you currently have, or are planning to buy, and identify the characteristics that make them useful for breeding. Then start matching them up with prospective partners. Just remember: Diploids can only be crossed with diploids, and tetraploids must be crossed with other tets. So know your ploidy. Does it matter which daylily is the pod parent and which is the pollen parent? There's an old saying that you get the plant habit from the pod parent and the flower from the pollen parent. I don't know if it's true, but it's probably worth considering.
3. Now you have your list of dream crosses. But, in reality, some of these won't actually happen because of factors beyond your control. For example, the daylilies might bloom at different times, or the cross might fail because of the weather, or the daylilies might not be compatible. We'll discuss how to deal with these problems later. The point is, you should plan some alternative crosses in case your dream crosses fail.
4. In the end, don't get stressed out. Remember that professional hybridizers grow out thousands of daylily seeds every year, but only a few seedlings are deemed worthy of introduction. So make it your top priority to just have fun!
Part Two: Collecting and Storing Pollen
1. Contact lens cases make good storage containers. You can buy them cheap from your local pharmacist. Cut them in half to make single storage containers, and number them with a Sharpie permanent marker. Make a numbered list of your pollen parents to correspond with the numbers on the cases.
2. Collect pollen in the morning after the daylilies are fully open. The pollen is ready to harvest when it appears dry and fluffy. But don't wait too long, or the bees will get it. When there's a daylily I really need pollen from, I go out early in the morning and cover the flower with a piece of fine mesh cloth, attached with a safety pin, to keep the bees off until the pollen is ripe.
3. Grasping a stamen, slide your thumb and forefinger up the filament, and pop the anther off into a contact lens case.
4. Set the open case in a room with good air circulation where the pollen can dry for 24 hours before freezing it for long-term storage or keeping it in the fridge for up to one week.
5. Close the case, and store it in the freezer in a ziploc bag. Additional dried pollen can be added to the same case on subsequent days, but don't let the frozen pollen thaw out. Return it immediately to the freezer. Frozen pollen should remain viable for up to nine years.
Part Three: Pollinating Daylilies
1. Pollination is usually done in the morning soon after the pod parent has opened. The stigma is receptive when it appears moist. If the stigma is dry or slightly shrivelled, use scissors to snip off the end before pollinating it.
2. If the pollen parent and the pod parent are blooming at the same time, simply pluck one of the stamens from the pollen parent, and brush the pollen on the stigma of the pod parent.
3. To use frozen pollen, remove an anther from a contact lens case, thaw it in a small bowl or an empty contact lens case for a few minutes, then use tweezers to hold it as you brush the pollen onto the stigma.
4. If the cross is successful, a pod will begin to form at the base of the faded flower within a few days. If not, the faded bloom will fall off.
5. If a cross fails to take after several attemps, consider these possibilities: Either the stigma is too long or too dry (try cutting it before pollinating), or the weather is too hot (try shade cloth, and make sure the daylilies are kept moist at the root zone), or the parents are incompatible or infertile (try a different pollen parent).
6. Some daylilies simply won't set pods in hot weather, and they are best pollinated in a greenhouse or a cool basement. Many hybridizers grow their daylilies in 2-gallon pots and bring them indoors to make crosses.
Part Four: Collecting and Storing Daylily Seeds
1. Daylily seeds should be harvested when the pods just start to split open, but before the seeds fall out. Check the pods every day once they have reached their full size. Before they split open, they'll start to shrivel slightly and lose their bright green color.
2. When a split appears in the pod, pop it off the stem and remove the seeds. Discard any mushy or shriveled seeds. Good seeds are plump and firm. If you will be planting the seeds soon, let them dry overnight, then refrigerate in plastic ziploc bags labeled with the cross. Place a small slip of paper or a piece of paper towel in the bag with the seeds to absorb excess moisture. Refrigerate for at least 3 weeks before sowing for best germination.
3. If you won't be starting the seeds until spring, dry them for 4-5 days in a well-ventillated room to prevent them from molding during storage. Store the seeds in the fridge until you're ready to plant them. Dried seeds should remain viable for at least one year. Check the seeds frequently, and discard any that are mushy or hollow. If the slip of paper is damp, replace it with a fresh piece. If any seeds sprout during storage, pot them up immediately. If mold develops, wipe it off with a damp cloth. A little mold is usually not a problem, as long as the seed is not mushy.