Planting flowers

March Gardening Checklist

We are going to touch base on four key tips that everyone should have on their checklist for March St. Louis gardening.

Tip #1: Clean up from Winter

  • Clean up any garden beds left over from winter. Cut back browned-out ornamental grasses and foliage of perennial flowers that you didn’t remove in fall, some of this may be removable by raking. Compost the dead foliage.
  • When new growth on roses is noticed, remove their winter protection, prune, and fertilize as needed.
  • Divide summer and fall blooming perennials as soon as you can work the soil.

Tip #2: Tend to the Garden & Landscape

  • When the soil temperature reaches 40 degrees F, fertilize your trees and shrubs before new growth begins.
  • Pull any weeds that survived or sprouted over winter. They’ll also come out easier in the soft, damp soil than in summer. Wait until warmer weather to add new mulch, though.
  • For established shrubs and perennial gardens, a fully blooming forsythia is your cue to apply a weed preventer.
  • Apply weed preventer around trees, shrubs, and established plants to prevent weeds for up to six months. The mulch also has the added benefit of helping the soil retain moisture and stay cool when temperatures heat up.
  • DO NOT prune spring-flowering shrubs now. Wait until about a month after they bloom. Pruning now may remove this year’s flowers.
  • DO NOT remove the foliage on early-blooming bulbs until it turns yellow or brown and falls flat, called ripening. The foliage replenishes the bulb with nutrients needed for next year’s blooms.

Tip #3: Plan a New Garden

  • Attend a flower and garden show in your community. There, you will learn about new plants, garden design, and solutions to landscape problems.
  • Test leftover garden seeds for germination. Place 10 seeds between moist paper towels, or cover with a thin layer of soil. Keep seeds warm and moist. If fewer than six seeds germinate, buy fresh seed.
  • In the South, seeds for warm-season flowers and vegetables can be started indoors in early March. For colder climates, wait until mid-to-late March or early April. Check the seed packet for precise instructions. Don’t transplant warm-season plants outdoors until all threats of frost have passed.
  • Use a hoe, ice-chopper, or edging tool to cut sharp edges around all the garden beds. Once the ground thaws, it’s soft and easier to slice than later in spring when it dries out and firms.
  • Plant new bare-rooted trees and shrubs.
  • Plant cool-season annuals, such as pansies, snapdragons, nemesia, and osteospermum.
  • When new plants are 2 to 3 inches tall, apply a garden weed preventer to prevent weeds all season long. In vegetable gardens, apply vegetable garden weed prevention.

Tip #4: Start the Veggies

  • Throughout the South, the Eastern Seaboard, and the lower Midwest, plant cool-season vegetables, including lettuces, peas, broccoli, cauliflower, Brussels sprouts, and spinach. Potatoes also can be planted this month. In the upper Midwest and north, wait until late March or early April to plant these crops.
  • Apply vegetable garden weed preventer around established plants that are 3 inches tall. Always read and follow label directions.

St. Louis landscaping tips