Propagating Native Wildflowers
Sleepy Cat Farm has been building its stock of native wildflower ephemerals the past few years to create an early layer of not only interest, but nectar sources for both native pollinators and domesticated honey bees.
Some of the early nectar sources that we grow are not native, for example Hellebores or Lenten Roses. These provide early nectar and pollen for insects and give us a long flowering season. Newer cultivars have attractive colored or variegated foliage, which further extends the season of interest.
Hellebores are simple to propagate from seed, so seedlings can be collected and grown by harvesting under mature clumps, or collecting seeds as they ripens, sowing in compost in flats in May and leaving them outdoors in a shaded frame protected from Rodents. Most wildflowers can be grown this way, although germination is sporadic and may take place over a year or two. Covering the frames with hardware cloth is a good idea. Rodents love to bury things in loose soil!
I should mention here, that propagating plants this way (called sexual reproduction) will often yield plants differing from the parent (much like humans). Flower color, habit, and leaf color may all be lost or enhanced! This is how many cultivars are bred, and enthusiastic gardeners often tilt the scales by controlling who or what creature visits the flowers during pollination.
If you want to create clones of the same type, this method is called asexual reproduction. Division, stem, root or leaf cuttings and even tissue culture are examples of this. Tissue culture is done under sterile laboratory conditions much like in vitro methods of cloning. This can produce very high numbers of plants from very small samples and is the most common commercial method with plants like Rhododendrons and Orchids.
My favorite time to increase stock of mature clumps of wildflowers is right now – mid-April through mid-May. I like to have consecutive days of cool cloudy, and even better, rainy weather. This allows the plant to recover quickly.
All one needs is a bulb or wooden crate lined with sphagnum moss, moistened. Find relatively mature clumps of plant on property you own or have permission to be on. Dig up the entire plant and gently wrestle small side divisions off the mother. Replant the mother and nest your new propagules into your crate and replant them. I like to add some composted leaves to the soil – preferably soil from the old hole as well. Some plants need the beneficial fungal mycorrhizae in order to establish. This is especially true with things like terrestrial orchids.
Some of the plants we divide this way are Asarum (wild ginger), Solomon’s Seal, Primrose, Trillium, Bloodroot, Jeffersonia, Ferns, Lungwort, Jacob’s Ladder, and Mayapple.
For very slow growing plants that you don’t have a lot of material to choose from you can dig up the plant, find one or two of the thickest roots—don’t remove more than 20 % – and replant. Take those roots and lay them horizontally in the ground or a tray in your frame. Cover with soil, protect, label and wait for new plants to emerge. This can be done with all the above, as well as shrubs. Suckering shrubs, like Lilacs, Dogwood shrubs, an even Rhododendrons can be increased this way. The best time to do this is often when planting a new plant from a container nursery. I will tease the roots prior to planting, remove one or two, and plant all. Always water everything in well.
Soon, if you want to increase your woody plants, we will show you how to propagate plants from stem cuttings, another type of asexual reproduction.
The two best books I have found for information on increasing native plants and wildflowers are both by William Cullina, currently the Director of the Coastal Maine Botanical Garden.