It is possible to breed and select cuttings from hemp plants that grow, flower, and mature faster. Some hemp plants will naturally be better than others in this regard, and it is easy to select not only the most potent hemp plants to clone or breed, but the fastest growing/flowering hemp plants as well. Find your fastest growth plant, and breed it with your “best high” male for fast flowering, potent strains. Clone your fastest, best high plant for the quickest monocrop garden possible. Over time, it will save you a lot of waiting around for your hemp plants to mature.
When a male is starting to flower (2-4 weeks before the females) it should be removed from the females so it does not pollinate them. It is taken to a separate area. Any place that gets just a few hours of light per day will be adequate, including close to a window in a separate room in the house. Put newspaper or glass under it to catch the pollen as the flowers drop it.
Keep a male alive indefinitely by bending it’s top severely and putting it in mild shock that delays it’s maturity. Or take the tops as they mature and put the branches in water, over a piece of plate glass. Shake the branches every morning to release pollen onto the glass and then scrap it with a razor blade to collect it. A male pruned in this fashion stays alive indefinately and will continue to produce flowers if it gets suitable dark periods. This is much better than putting pollen in the freezer! Fresh pollen is always best.
Save pollen in an air tight bag in the freezer. It will be good for about a month. It may be several more weeks before the females are ready to pollinate. Put a paper towel in the bag with it to act as a desecant.
A plant is ready to pollinate 2 weeks after the clusters of female flowers first appear. If you pollinate too early, it may not work. Wait until the female flowers are well established, but still all while hairs are showing.
Turn off all fans. Use a paper bag to pollinate a branch of a female plant. Use different pollen from two males on separate branches. Wrap the bag around the branch and seal it at the opening to the branch. Shake the branch vigorously. Wet the paper bag after a few minutes with a sprayer and then carefully remove it. Large plastic zip-lock bags also. Slip the bag over the male branch and shake the pollen loose. Carefully remove the bad and zip it up. It should be very dusty with pollen. To pollinate, place it over a single branch of the female, zipping it up sideways around the stem so no pollen leaks out. Shake the bag and the stem at the same time. Allow to settle for an hour or two and shake it again. Remove it a few hours later. Your branch is now well pollinated and should show signs of visible seed production in 2 weeks, with ripe seeds splitting the calyxes by 3-6 weeks. One pollinated branch can create hundreds of seeds, so it should not be necessary to pollinate more than one or two branches in many cases.
When crossing two different varieties, a third variety of plant will be created. If you know what characteristics your looking for in a new strain, you will need several hemp plants to choose from in order to have the best chance of finding all the qualities desired. Sometimes, if the two hemp plants bred had dominant genes for certain characteristics, it will be impossible to get the plant you want from one single cross. In this case, it is necessary to interbreed two hemp plants from the same batch of resultant seeds from the initial cross. In this fashion, recesive genes will become available, and the plant character you desire may only be possible in this manner.
Usually, it is desirable only to cross two strains that are very different. In this manner, one usually arrives at what is refered to as “hybrid vigor”. In other words, often the best strains are created by taking two very different strains and mating them. Less robust hemp plants may be the result of interbreeding, since it opens up recesive gene traits that may lead to reduced potency.
Hybrid offspring will all be very different from each other. Each plant grown from the same batch of seeds collected from the same plant, will be different. It is then necessary to try each plant separately and decide it’s individual merits for yourself. If you find one that seems to be head and shoulders above the rest in terms of early flowering, high yield and get buzz, that’s the plant to clone and continue breeding.
In depth genetics is beyond the scope of this work. See hemp Botany; Smith, for more detailed info in this area.