Photo and article by Joyce Rapp, Goodhue County Master Gardener
Assuming you have prepared your beds with the proper soil and mulch, the following tips will help to care for your perennial plants:
- Weed – Controlling weeds is one of your most important tasks. This prevents weed seeds from germinating. Pull them by hand or use a hoe to scuffle the surface.
- Mulch– Spread 2-3 inches of mulch annually to prevent weed seeds from germinating, to keep soil temperature more consistent help retain moisture.
- Water – Once established, perennials usually need very little supplemental watering. Plant your perennials in groups that use similar watering requirements. Water infrequently and deeply from below. Inspect 2 inches deep into the soil to check if watering is needed. Morning is the best time to water to prevent fungal diseases.
- Fertilize– Extra nutrients should not be necessary for most plants if you prepare your beds correctly. Some heavy feeders including phlox, day lilies, daisies, and hibiscus may need to be fertilized – take a soil test to know for sure.
- Groom– Thinning, pinching or trimming, disbudding, deadheading and staking are all methods to improve the appearance of your plants. By shearing the following plants early in the season, you can produce a stronger stemmed plant: aster, Rudbeckia, catmint, coneflower, mallow, Monarda, rose mallow, Sedum ‘autumn joy’.
- Inspect for insects –Observing insects on plants does not mean there is a problem – many insects are beneficial. Check with a nursery, garden book or county extension office for identification. If needed, use the least toxic method of eradicating harmful insects.
- Prepare for winter– Mulch only after a hard frost as mulching too early can produce new growth that will be killed by a hard freeze. Water perennials before a hard freeze. Do not fertilize from early fall on. Trim back foliage to prevent disease from setting in during the winter. Ornamental grasses can be left standing and trimmed in the spring.
Remember that right planted in the right plant in the right place will result in little or no major problems. Proper light, drainage, soil type, and zone are needed. Native plants are adapted to the local area and are always a good choice.
This is one of three articles on perennials based on information by: Janet Macunovich: Ten Tips on Dividing Perennial Plants http://www.finegardening.com/how-to/articles/dividing-perennials.aspx and Perennials for Minnesota and Wisconsin (Don Engebretson and Willaimson.)