Spring Perennial Care Tips

With our warmer than average spring, perennials are starting to emerge. Now is a good time to begin a bit of spring perennial care. Here are five tips:

Cut back last year’s growth. I’m on the fence on when it is best to do this. Many gardeners who are interested in helping beneficial insects, say it is best to leave last year’s plant growth up until well into May. If you do cut back stems of sedum and other plants, you can leave them on the ground to provide shelter for insects until the temperatures have warmed more.

Remove mulch. If you mulched around more tender perennials, now is a good time to remove it or at least fluff it up to give the plants some air. Once the ground warms up, the mulch is less effective and, if it is wet out, may even encourage mold. Gardeners located in northern Minnesota may want to leave mulch on a bit longer as temps can still dip fairly low at night.

Water. We are about an inch short of average on rain in the month of April, so you may need to supply some extra water to get perennials off to a good start. Unlike annuals in containers, perennials do not need regular watering. If the soil is dry 4 to 5 inches down or if the plants seem droopy, give them a good drink.

Divide. Some perennials get pooped out after a long time in one spot and spring is a great time to divide them to reinvigorate the plant and share the divisions with other gardeners (or just move them to a new spot in your garden.) How can you tell if a perennial needs dividing? Look for the doughnut. If there is a hole in the center of the plant as it comes up in spring, it’s a good time to divide the plant.

Fertilize. Not all perennials need annual fertilization. Prairie plants, such as coneflowers, rudbeckia and blazing star, do best in a lean soil. Others do well with just a light sprinkling of compost or a slow-release fertilizer. If you are buying fertilizer, look at the three numbers on the package. If the first number (the nitrogen) is largest, that will promote leaf growth. The second number (phosphorus) will promote more blooming. You can over-fertilize, so consider how rich your soil is and never exceed the package recommendation.