The flowering shrub spirea is among the easiest flowering shrubs to grow because they are such tough and hardy plants. All 80 species of spirea are members of the rose family and are characterized by their petite leaves emerging from a mass of twiggy branches. This article explains how to grow spirea from seed in only four simple steps.
Step One; Germinate Spirea Seeds
In order to increase your probability of successfully propagating a healthy and mature spirea bush, the first year of the plants life should be spent in a container. Container gardening gives you the ability to control almost every aspect of the young plants life. Planting spirea seeds directly in the ground leaves the tender plants to fend for themselves against the forces of nature.
Seed starting or “germination” should be executed during the first week of spring after the threat of winter frost has diminished. To germinate spirea seeds, sandwich them in between several layers of damp paper towels and place them in a warm dark area of your home until a sprout appears.
Step Two; Prepare Containers and Plant Sprouted Seeds:
Acquire two twelve inch pots and fill the bottom inch of each with gravel to ensure proper drainage. Fill the remaining space in the pots with a high quality organic potting soil mixture. Spirea plants will tolerate a large range of soils however—since you’re starting from seed—it is best to use the highest quality soil available. Choose a well draining soil that is equipped with a time release fertilizer.
Plant the sprouted seeds into the prepared containers exactly how it is prescribed on your seed packet. Since there are numerous species and varieties of spirea, it is impossible to generalize about the proper depth and space to plant seeds. After planting, cover the top of each container with a layer of plastic wrap to increase humidity and set the pots in the sun.
Step Three; Thin Seedlings and Provide Care:
Once foliage emerges from the soil in each pot, the plastic wrap should be removed immediately. The seedlings must be thinned after the seedlings have grown at least three inches. Thin the seedlings according to what is prescribed by your seed packet, being sure to save the strongest growing seedlings.
You may choose to plant seedlings in separate containers while thinning. Planting seedlings in separate containers is a good idea because it gives each seedlings root system room to grow and makes it easier to transplant the plants outside when appropriate.
Step Four; Raise Seedlings for a Year:
Raise your spirea seedlings in their containers for at least an entire year before transplanting them into the ground. After thinning the seedlings, they should be fairly established and require minimal care. Keep the seedlings in partial sun and water them every other week. Since spireas aren’t heavy feeders you need not worry about fertilization until they are planted outside. However, if you wish to fertilize your seedlings, use liquid fertilizer once every other month during watering.