How to Care for Perennials

Last updated December 13, 2023
A garden filled with perennials will delight year after year, as plants like hosta and coneflowers grow and thrive. Unlike annual flowers that bloom for a single season, perennials will give you all they’ve got one year, go dormant in winter and will return the following spring, ready to put on a show all over again.
Perennials can be low-maintenance, but that doesn’t mean no maintenance. Sometimes, despite your best efforts, pests and diseases will attack the plants, and plants will fail to thrive in their location. With a few tips, you can learn to treat and prevent problems before they begin.
Table of Contents
Know What You Grow
Right Plant, Right Place
Divide to Conquer
Troubleshooting Perennials
Take a Look
Common Problems
Know What You Grow

The first step is to know the plants that you grow and be sure they’re perennial in your hardiness zone. Often, plants that are reliable perennials in warm climates are treated as annuals in colder climates. After all, the most popular annuals, like impatiens, petunias and begonias, are native to tropical areas.
When shopping in the Garden Center, let plant tags be your guide. Learn more about the differences between annuals and perennials.
Right Plant, Right Place

Seasoned gardeners talk about putting the right plant in the right place. This means knowing the light and soil in your garden and making smart choices about what you plant. For example, planting hosta in full sun is almost always a mistake.
Unlike annuals that, for the most part, love and demand lots of sun, perennials tend to like a variety of conditions from sunny to shady and all lights in between. Popular perennials grown throughout the country include sun-loving coneflowers, daylilies, daisies, Black-eyed Susans and coreopsis. The most popular perennial for shade, of course, is hosta, but there are more low-light favorites including astilbe, heuchera (coral bells), hellebores (Lenten rose) and Lily of the Valley.
Keep in mind soil type when growing perennials. For example, hostas like moist shade, and heucheras tend to like dry shade. And all plants like soil amended with organic compost.
Divide to Conquer

Throughout their life, perennials need water, light and fertilizer to grow and thrive. Unlike annuals that get tossed in the compost pile at the end of the season, perennials continue to grow in place. That’s why every two or three years, you’ll need to divide them. There are two optimal times for dividing perennials: in fall just before they go dormant, and in very late winter as they're just waking up.
Dividing perennials is necessary to avoid overcrowding and to keep your plants healthy. Plus, you get bonus plants for your own garden or to share with fellow gardeners. You can tell when a plant needs division if it develops a dead core in the center of its crown. Also, if the foliage is fairly lush but the plant is producing steadily fewer flowers each year, it's time to divide.
You can divide perennials in late winter and early spring as long as the soil is workable. Make it easy on yourself and garden on a day after rainfall.
Tip: Slicing through tough stems and roots requires tough tools. A hori-hori garden knife or a similar all-purpose garden tool gets the job done. Some nursery pros recommend using a sturdy, inexpensive serrated bread knife to divide perennials.
Troubleshooting Perennials

It’s important to understand that plants will sustain some damage in their environments. Insects nibble on foliage, flower buds turn mushy in heavy rains, late winter storms freeze new growth. Just like our human bodies get bumped, bruised and bit as we maneuver through our environments, so do plants.
We keep our immune systems strong to fight off infections and to heal quickly. The same is true in the garden: give plants healthy soil and enough sunlight, water and nutrition, protect them from opportunists like deer and squirrels and learn to tolerate minor imperfections. Most pest problems, like Japanese beetles in summer, come in for a week or two, then move on, and plants recover.
Take a Look

Find problems while they're still manageable when you make scouting trips through your garden.
Routine scouting is part of the gardening experience. Check leaves and blooms. Determine if plants need water. You may not see insects at first, but bend and look on the underside of leaves to see where the bugs like to hide. You may find a magnifying glass helpful for this task.
Common Problems

Learn to identify common pests, like aphids, slugs and whiteflies, and the damage they cause, such as aphids’ cottony webs and slugs’ sticky trails.
Some plants are more prone to diseases, like peonies are susceptible to botrytis blight. This disease occurs in damp rainy seasons and will destroy peonies from the ground up. Control botrytis blight with a fungicide application. Preventive measures include moving the plants to a sunnier location and amending the soil with compost to improve drainage.
In many cases, the solution to the problem is a control like fungicide, but can include preventive measures like site improvement, routine care like fertilizing and pruning, and amending the soil.
Perennials can sustain damage from pests like deer, squirrels, rabbits, voles and mice. You’ll notice this with plants like hosta being chewed down to nubs. There’s plenty of controls for pest damage, organic and non-organic. Most effective controls are a mix of several methods. Begin with organic methods first before resorting to chemical solutions.
You can nurse injured plants back to health by trimming off damage, refreshing mulch and tending with a top dressing of compost. Perennials are by nature resilient plants, and if they have strong roots and good weather, they will come back again.
Whether you need the right planters, seeds or potting soil, The Home Depot delivers online orders when and where you need them.