Growing Rain Lilies From Seed
This summer and fall, try your hand at growing more rain lilies from seed. They can be very attractive grown in drifts or clumps among other short annual and perennial plants in the flower beds, or sprinkled out into the "root flare" areas around the trunks of deciduous trees, where their bright, twinkling flowers add interesting touches of white, yellow, or pink to the edge of the lawn area. Easy to obtain rain lilies such as Habranthus robustus (clear pink flowers with a white center) and H. brachyandrus (darker pink with a maroon center) have slender leaves about 6-8 inches long and large, funnel-shaped flowers, and are well adapted to our area.
Collect & store fresh seeds in a paper bag
The Zephyranthes are rain lilies from Mexico, Texas, and Argentina that have a range of colors from white through yellow, red and pink with multiple flushes of flowers during their blooming season. Central Texas favorites include Z. smallii, Z. jonesii, Z. morris-clintii (red or yellow form), and the large white "Giant Prairie Lily" (Cooperia drummondii, Cooperia pedunculata). These may be seen in pastures and along the roadsides in large, spangled masses after rains at the appropriate time of year and are easily transplanted to the garden. They have the added attraction of a lily-of-the-valley fragrance. Galveston, Texas is a good hunting ground for the small but scented white Z. traubii.
Another fairly recent addition to the list of available rain lilies are the 'La Bufa Rosa' crosses, created from Zephyranthes species that grew and mixed when in close proximity in the area of Mexico near Tamaulipas, and have now been bred up into distinct strains. These tend to go completely dormant at times during the year and to burst into flower with mid-summer or early fall rains.
All of the above rain lilies make excellent garden subjects, as long as they are not disturbed by mistake during dormancy. They adjust nicely to more alkaline soils, unlike the Atamasco rain lily, (Z. atamasco) which is found from Maryland to south of Florida.
Blooming cluster of H. brachyandrus
Disappointingly, two of the rain lilies that are especially showy, the rich pink Z. grandiflora and the silvery-white Z. candida, do not set seed under ordinary garden conditions.
Collecting Seeds - The seed pods that form after flowering are capable of maturing within a week or ten days. The tri-part pods suddenly burst, allowing several dozen flat, stacked, winged black seeds to escape from each pod. It's best to pick the pods while they are still closed but have begun to turn yellowish in color. They'll continue their final maturity after picking, and won't be lost onto the ground. Collect into a small paper bag, not plastic, so that the seeds can dry. A plastic bag will encourage spoiling. Store them during the short ripening time in an area that is out of the hot sun with good air circulation to prevent mildew.
Seeds of bulbs in the Amaryllis family do not keep well over time, so plan to sow your bounty as soon as possible after the pods have burst open. Use shallow terra cotta or plastic pots, or, if you have a lot to sow, plant into a flat plastic pan such as a kitty litter container. Poke holes into the bottom of the pan with an icepick so that water will drain out easily.
Fill the flat or pot almost to the top with a mixture of good potting media and coarse sand, and water thoroughly. Press down the surface firmly. Sprinkle out the flat black seeds so that each has a little room to grow. Drizzle more of a mixture of potting soil and sand over the top to cover the seeds. Press down very gently. It may not be necessary to water again. Attach a label with details on variety or cross, or source of the seed if you have ordered them from an online group such as the Pacific Bulb Society, whose offerings are sent in by the various members. If you know the name of the original donor, put that on the label as well, along with the date.
Rain lilies from seed
Pots may be inserted into a thin plastic bag such as those from the produce department of the grocery store. These are said to 'breathe'. The label and a small stick or two will be enough to keep the plastic from falling down onto the surface of the container. For larger flats find larger plastic bags, if possible, or seal over the surface with saranwrap. Set the containers away in an area with bright indirect light - never in full sun. they may even be placed under shrubbery in the garden for the period of time while they are germinating. Expect results between two and four weeks of planting. If the seal is tight, you may not have to re-water at all during this time, but if you see that the beads of moisture that have collected on the inside of the bag have disappeared, you could take the container out of the bag and gently immerse it into water almost up to the rim for a few minutes.
After the slender green leaves have appeared, you may take off the wrappings and water occasionally from underneath with tepid rain water, adding a small amount of weak fertilizer to the water weekly. Try to keep the pots of seedlings growing as long as you can, because going "dormant" and re-sprouting again takes much of the small reserves of energy the seedlings have built up. In the spring of the next year you may spread the seedlings out into a larger container and keep them well watered and well weeded until the leaves reach a length of several inches.