Note: It is illegal to collect seed from the wild in many cases unless you own the property or have permission from the owner. Collecting wild seed can endanger natural plant communities and even where seed is abundant is discouraged by naturalists and ecologists in any but modest amounts on private property. It is not permitted at all on protected lands such as our National Forests, State Parks, and preserves such as those of The Nature Conservancy.
I’ve noticed masses of small pale purple flowers along streamsides, in ditches, and low-lying areas around Floyd County. I believe these are our native Symphyotrichum puniceum, Purple-stem Aster, often called Swamp Aster though not by the Flora (read more).
I plan to collect seed in about a month once the seedheads have dried, since we have some growing above one of our roadside ditches. These like many native perennials require 60 days cold moist stratification, so I will start them in damp sand in the refrigerator probably in February with plans to plant in April when the nights are still cool. Prior to stratifying them, I’ll store the seeds in a paper envelope or ziploc baggie in a cool dark location.
Cold Moist Stratification
To cold moist stratify: I like using a steel mixing bowl and dry sand, thoroughly blending seeds into the sand, sprinkling sparingly with water until damp but not wet, then spooning the mixture into a ziploc bag. The bag is labeled with the name, date, and any other notes, the calendar marked for 60 days later, and the bag placed in the back of the fridge. Based on past experience with Symphyotrichum pilosum, I will not stratify a great quantity of seed, as I got bumper crops from only about 6 or 7 small flower heads.
To plant, good seedling or potting medium is filled and settled in a seedling tray supported by a daisy tray, and the medium is watered until well moistened if needed. Then the sand/seed mixture is spread across the surface of the tray until evenly distributed (this is an inexact science and not as tricky as it seems at first), and the whole tray is deeply but gently watered in with the mist setting on the hose.
Trays are set outdoors to sprout, which may take as long as 6 weeks or as little as 2 (I have not sprouted this species before). Setting on a table or off the ground will protect seedlings from slugs, especially if the legs of the table are set into water-filled containers. Overhead protection able to withstand hail and torrential rain is strongly recommended given Floyd’s propensity to stormy spring weather. Anything from a greenhouse to a brightly lit covered porch to a wire cage with row cover will do, so long as it allows light through and doesn’t interfere with watering.
Once seedlings sprout, after the second set of leaves has emerged, they can be transplanted into larger containers to grow large enough to plant. We used deep cell plug trays, my favorite for efficiency of space and soil as well as for producing a very sturdy plant that is much easier to transplant than larger pots. But you could plant into any kind of pot or container you like. Water every day until planted.
Planting time depends on root development and your ability to keep them watered until established. Maya Skopal once told me she plants native plants all year round and I’ve found this advice to be true. Not into frozen or sodden ground, but much of the year in Floyd the ground is pliable enough. Even during the height of summer you can have success so long as you water them the first few weeks and again during drought.