Like HowStuffWorks on Facebook!

Tips for Growing Annuals and Biennials


Gardening Tips for Annuals and Biennials
Plant annuals and biennials in your garden and you'll enjoy an incredible variety of beautiful, colorful flowers. The following gardening tips will help you grow strong, healthy plants.

  • Gently break up the root ball of annuals grown in cell packs or pots before planting them. Often, the roots have overgrown the potting area and become matted. You'll have to pull off the tangles so the roots will be able to grow free into the soil.
  • If roots are wound around the bottom of the root ball, use your finger to gently work the roots free of each other. If they are matted over the entire root ball, you'll need to tear or cut the mats off, leaving the roots below intact.
  • Snip back leggy annuals when you plant to encourage bushy new growth. Don't hesitate -- it's really for the best! Removing the growing tip of a stem stimulates side shoots to sprout, which makes annuals fuller. Since each side shoot can be full of flowers, the whole plant will look better.

root ball
The root balls of annuals should be broken up before planting.

  • Fertilize annuals periodically during the growing season to keep them producing. This is particularly helpful after the first flush of blooming flowers begins to fade (which often marks the beginning of a quiet garden during hot summer months).
  • Remove spent blossoms from geraniums and other annuals to keep them blooming and tidy. The bigger the flower, the worse it can look when faded, brown, and mushy. Large, globular geranium flowers are particularly prominent when they begin to discolor. Snip off the entire flower cluster. Take off the stem, too, if no other flower buds are waiting to bloom. This process, called deadheading, is more than mere housekeeping. By removing the old flowers, you prevent seed production, which consumes a huge amount of energy from the plant. Energy saved can be channeled instead into producing new blooms.
  • For best results, deadhead, then fertilize with a balanced water-soluble or granular fertilizer. A balanced fertilizer contains similar percentages of nitrogen, phosphorus, and potassium. Check the fertilizer package label for application instructions.
  • Pinch annuals like coleus, browallia, and petunias to keep them full. These plants can get tall and gangly as the growing season progresses. A little pinch, removing the top inch or two of stem, will soon correct this problem. More is at work here than merely shortening the stem. Removing the terminal bud (at the stem tip) allows side branches to grow and make the plant fuller.
  • Plant naturally self-branching annuals. Your mother may have pinched all her flowers throughout the summer. But many modern types of impatiens, begonias, multiflora petunias, and other annuals have been bred to be self-branching. They stay fuller naturally and may not need any pinching, or at least very little.

In our final section, we'll talk about working with stem cuttings.

Want more gardening tips? Try:

  • Gardening Tips: Learn great helpful hints for all of your gardening needs.
  • Annuals: Plant these beauties in your garden.
  • Perennials: Choose great plants that will return year after year.
  • Gardening: Discover how to garden.