Daylilies can be propagated in a number of ways, both sexual and asexual or vegetative. With sexual reproduction the genetics of the seedlings will be the combined DNA of both parents. Hybridizers have created close to 30,000 registered hybrids. There is no way to know how many non registered hybrids have been created and are growing in people gardens all over the world. In asexual or vegetative reproduction the genetics of the new plants will be clones and identical to the parent plant.

Division

After a few year a well growing established clump of daylilies is going to need dividing. Division is the easiest and most common way to get new plants. Undivided daylilies will decrease in vigor and produce fewer flowers after a number of years so its a good practice to divide them regularly.

Depending on who your talking too, daylilies can be divided in the spring or in the late summer to early fall. There are good points for dividing them in either time periods. In the early spring when the sprouts are just coming up is a good time to divide, you can see where the fans are located. The plants are in a quick growing period so they will recover quickly. The smaller leaves will prevent a lot of water loss as the roots re-grow. The soil is usually damp from all the rain and melting snow so the transition in and out of the ground is easier on the plant. You will not have to water as often because of the normally heavier rainy days in the spring.

Late summer and early fall are also ideal times to divide your plants. There still is enough time for the plants to get settled before winter, the summer blooming is over so the plant can spend all its energy in putting down new roots. In the colder climate it is best to not wait to long before doing the dividing, the plants will need at least six weeks to get re-established.

When dividing up a clump you can break it down to single fans but these may look skimpy and take a few seasons to grow to blooming size. It is best to keep them to a minimum of two fan, three or four would be better. Larger clumps have a larger root system which reduces the timeframe need to re-establish the plants.

To divide a clump there are a number of ways. If you do not want to move the clump totally you can take a garden fork and pry groups from the outer edge. When a clump is to be totally divided it is better to dig up the entire clump first.  Remove the soil from the roots so you can get a better look at where the crown is located. Some gardeners then take a flat shovel and cut the clump down the middle. This method can do allot of damage to the clump and slice off some roots. Another way to divide the clump in half is to use two garden forks that are back to back in the clump. You then push the handles away from each other. This pries the clump apart and does not damage the roots. The clump can then be divided into smaller groups using the same method. If you wan to get down to your groups of two to four fans at this point you can pry them apart by hand or cut them with a sharp knife.

Once you have your larger clump divided it is a good idea to soak the division in a fungicide solution or apply a fungicide powder to the newly made wound in the plant. It is a good idea at this point to cut the leaves back to approximately one third to one half their length. The reason for this is water is lost from the leaves through a process called Transpiration. By reducing the leaf size the water loss is decreased and the plant is not as stressed while it tried to re-grow its root system. Some gardeners cut back the roots as well at this time. This is promote new root growth just above the point where the roots have been cut off. If your going to trim your roots, you must cut back your leaves to balance out the plant. This is the same process you would perform then trimming the roots on a house plant.

At this point treat the division like you would a newly ordered plant from a nursery. You can apply a high phosphorus fertilizer at this time to speed up root growth.

Proliferations

Proliferations are small plants that occasionally grow about halfway up the scape of a blooming or just about the bloom daylily. The are basically miniature daylily plants complete with a small crown, leaves and if left long enough sometimes may grow roots. Not all cultivars grow proliferation, but some seem to grow them on just about every Scape. You will normally find the proliferation coming from the bract on the scape.

Once the proliferation is well developed you can but scape just below the bract. Them trim off the rest of the scape but leave a small piece that holds the proliferation. If the proliferation has some roots already developed then it can be potted up in a light seedling mix and grown under lights or in a greenhouse like a seedling. Make sure you label the pot so you know which cultivar it is. If the proliferation does not have any roots at this time you may have to dust the bottom end with a rooting hormone for softwood or semi-hardwood cuttings.

Plant the cut end into the growing medium at least 3/4 of an inch. Growing medium can be seedling mix or you can use a mixture of sterile perlite/vermiculite. The proliferations will been to have a constantly moist growing medium and a fairly high level of humidity in the surrounding air. The high humidity can be achieved in the house by putting a clear plastic sheet over top of the pot, or the the transparent lid for flats that come with them. Place them under lights or in a window that get lots of light but no direct sunlight. The roots should develop in a few weeks. Keep an eye for any fungus that may develop in the covered pot or flat.

In warmer climates the proliferations can be grown outdoors if they have roots. In the northern climates it is best to grow them indoors or in a greenhouse if you have one. They should be ready to plant in the garden by the spring.

Tissue Culture

Tissue culture of daylilies has taken the commercial gardening industry by storm. Literally hundreds of thousands of daylilies are now being produced by this method. In theory the plants should be genetic clones of the parent plant. But, the reality is while they might be genetically identical to the parent plant, not all of the tissue culture specimens grow and bloom true to type.

In tissue culture a tiny piece of the plant, quite often a piece of the growing bud is sterilized, places in a test tube of sterile nutrient solution. The formula for the medium is customized  for each species of plant. The temperature, humidity and pH are carefully controlled. Even the water and air coming into the area is sterilized.

The tissue grows very quickly under these conditions as long as fungus does not develop. Once the tissue has grown large enough it is taken from the tube again in sterile conditions, cut into small pieces and places into a different growing medium in larger test tubes or beakers. These then start to develop roots and leaves. When they become small plants they can be removed and planted as small seedlings in pots or flats.

For allot of varieties of plants the tissue culture works very well and the plants grow true to form. Unfortunately for daylilies this is not true. Mutations have arisen often enough in the test tubes or propagation jars that many commercial growers are reconsidering carrying tissue cultured varieties. It seems some cultivars grow fine but others are not stable and no one really knows the reason. Several theories have been put forward but none have been proven to be the cause. I myself have had plants purchased in pots that I later found out were tissue culture that did not look like the picture I have seen in books and on website of the same plant.

Propagating by Seeds

Propagating by seed is the only sexual method of creating new daylilies. The offspring will not be identical to either parents but will be a joining of half the genetic material from both parents. With hybridizing the potential for new daylilies is unlimited. One does not need to be a scientist with a PHD is botany to be a hybridizer. Many beautiful cultivars are produced by people known as "pollen daubers", gardening enthusiast working in their back yards. Of course the really beautiful ones are from long term hybridizers working carefully for a specific goal. Because of hybridizing we now have new flower shapes like spiders, a new form called "Unusual Forms", characteristics such as ruffles edges, larger watermarks, distinct eye zones. Possibly the first blue daylily will be formed soon do to special breeding programs.

The first step in your hybridizing program is to choose the two plants you would like to crossbreed. If your very new to crossing more than likely your just going to cross your favourite plants with other that are your favourite and see what comes up. Serious breeders look at the characteristics of their plants, either larger flowers, certain shapes, colour, or designs to the flowers, number of branchings to increase bloom time. Once you figure out which plants you want to cross you need to choose which will be the pod parent and which will be the pollen parent. If you cannot decide why not just cross them both ways and see how the offspring differ.

The actual process of crossing two plants is quite simple. Take the pollen from one plant and place it on the pistil of the other plant. The result of any two crosses can be very different, even if two different people cross the same two plants.

One of the main things to look for is the ploidy of the two plants your crossing. Diploids can only cross with diploids and tetraploids with tetraploids. If by chance your daylily is a triploid such as H.fulva it can only be crossed with another triploid or a tetraploid.

Some hybridizers remove the male stamens off of the Pod Parent or plant that will be accepting the pollen from the Pollen Parent. Since the Pistil or female parts are much longer than the male Stamens it is not a necessity.

Another key point to successful hybridizing is to have the pollen mature when the pod parent is ready to accept the pollen. Daylilies bloom at different times of the season and the two you may wish to cross might on different schedules for blooming. If the pollen parent blooms well before the pod parent it is possible to dry out the pollen and store it in the refrigerator or freezer for longer storage.

To freeze pollen, remove the Anthers with tweezers and put them into a container. Old film canisters works very well, especially if they are transparent and you can write on them using a permanent maker. Mark the cultivar and date collected. When removing the pollen from the freezer to use let it equalize to room temperature before opening the container. Frozen pollen can be kept for many months to even years and can be thawed and refrozen for use a number of times. When using the pollen if you only need a little bit of pollen, use a small artist brush that is clean and dry. Make sure there is no other plants pollen to mix with the one your working with at the moment.

While most pollens are fertile, not all crossings will result in seeds. Some plants may not be pollen fertile but are fertile as pod parents. It is best to pollinate during the cool, moist parts of the morning. As the day progresses and temperatures rise, successful crosses become less likely.

Once you have successfully crossed the plants, you need to record the cross. Make a label starting with the pod parent then the pollen parent, also date the cross. A tie on tag works well.

Do not take the flower off the plant that was crossed, let it fall off naturally. You may pull off the ovary if you do. When the flower falls off an a couple of days, the ovary will start to swell if the cross was successful. It will take about 6-8 weeks for the seed pod to fully develop. The seeds will ripen inside over the season. When the seed pod is full ripened it will turn brown and start to split. Inside will be glossy black seeds. But be careful at this point as they can easily be scattered by wind, rain or being brushed by animals or people.

Once the seeds are ripe it is time to collect them. Place them in a container that can be labeled, either a plastic bag or an envelope. Place them in the refrigerator for a cooling period of a minimum of three weeks. It is a good idea to keep them moist. Research has suggested that dried out seeds do not benefit from the cooling period. Mix some mild fungicide with water and place it into the plastic bag with he seeds to keep them plump and fungus free.

After they complete their cool period, they can be planted outside in the spring or inside like other seedlings. I use florescent fixtures to start them inside. If you sow the seeds outside in the fall they do not need a cooling period in the fridge. There however are some draw backs to this. If they sprout before winter sets in they may not be sufficiently established to survive and you can lose them. Also you will lose the winter growing time, which can get them to blooming size quicker. If growing them inside treat them like any other seedling. Once spring arrives plant them in the garden and carry the labels so you know what you have crosses and where you have planted them. When planting them in the garden give them 6 in(15cm) in rows 12-18 in (30-45cm) apart. They may look small now but they need room to get to their mature size, which depending on the cross might be quite large. It will take from one to three years to mature and grow to blooming size. Once they do start to bloom you get to see the rewards of your work. It is a very exciting time.

This is a picture of my first blooming seedling. I was just playing around and took the seed pod that developed from a hybrid called "Catherine Woodbury". I just wanted to see if I could get a seed to germinate and grow to bloom size. The picture on the right is Catherine Woodbury and for the most part if looks very similar but the colour of the seedling has more purple in the petals.

Hybridizing is allot of fun and who knows what you can come up with right in your own back yard. I would recommend you give it a try. Maybe your efforts will yield something that everyone would be willing to grow.