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How to Plant an Annuals Garden


Planting and Caring for Annuals

Whether you started your plants inside as seeds or went to your local garden center for flats of your favorite annuals, you'll need to properly plant annuals and care for annuals in order to achieve the garden you've spent so much time planning for. Use the suggestions that follow to do just that.

Planting

Get your plants off on the right foot by taking care when planting annuals in your garden bed.

  • 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 freely 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.
  • Use a spacing aid to plant annual displays and cutting gardens in even rows. Even the most beautifully grown annuals can be distracting if they are spaced erratically. Fortunately, spacing is one element you can easily control. Here are some options:
  • Make a planting grid by stapling a large piece of wire mesh over a wooden frame. If the mesh openings are 2 inches square and you want to plant ageratums 6 inches apart, you can put one seedling in every third hole.
  • Make a spacing rope. Tie knots in the rope to mark specific measurements, for instance, noting every 4 or 6 inches. You can stretch the rope between two stakes to make even measurements along a straight line.
  • Take a yardstick with you when you go to plant. Measure the distance between each plant in a row and between rows rather than simply eyeballing it.

Zinnias benefit from proper growth care.
© 2006 Publications International, Ltd.
Zinnias benefit from proper growth care.

Watering

Along with soil and light, water is an essential ingredient for plant growth. It's not easy, especially at first, to gauge exactly when plants require water -- so much depends upon current weather and soil conditions.

The Benefits of
Deep Watering
When plants are watered infrequently but heavily, they'll develop large and deep root networks. Frequent light waterings cause plants to develop shallow root systems just below the soil surface. This causes plants to be poorly anchored and therefore subject to toppling in heavy wind or rain, as well as liable to wilting unless they're watered daily. Therefore, slow, deep-soak watering produces stronger and hardier plants. Whenever possible, water in the evening or overnight rather than in the morning or the heat of the day.

For example, if good soaking rains fall frequently, it's obvious additional watering is unnecessary. However, when there's a light rainfall every few days, it's possible that only the soil surface has been dampened without much water actually reaching plant roots, necessitating the addition of water.

Plants subjected to bright sun and wind also lose a lot of
water that needs to be replenished. Similarly, because trees continually pull large quantities of moisture from the surrounding soil, annuals planted near or under them need more frequent watering than those in the open.

All of these factors affect the rate at which soil dries out.
Some plants require soil that is constantly moist, while other species tolerate -- or even require -- some drying between waterings.

So how do you judge when to water and how much water to give? The one sure way to test is by poking your finger 2 to 3 inches into the soil and feeling how moist or dry it is. Taking a pinch from the surface isn't good enough; you need to know what it's like down in the root zone.

Inexperienced gardeners should check soil moisture any day that there is little or no rainfall. Over time, you'll develop a feel for the overall conditions and check only when you suspect the soil may be turning dry. Remember, it's always better to check too often rather than not often enough. Don't wait until drooping plants indicate that the soil is parched.

When you do water, water deeply. Many people briefly spray a thirsty flower bed with a handheld hose. When they tire of holding it, become bored, or think they have watered enough because the water has stopped soaking into the soil as rapidly as it did at first, the watering session is ended. Always pause to check how deeply the water has penetrated. Guessing usually results in reaching only the top 1/2 inch leaving the soil beneath it still dry.

A better approach is to use an automatic sprinkler, letting it gently "rain" for an extended period of time. Check at half-hour intervals to see how deeply the water has penetrated. Turn the water off when the soil is moistened to a 4-inch depth. Don't water again until your testing indicates the need.

One problem with sprinkler water is that the foliage becomes very wet, creating an ideal environment for the spread of fungus diseases. In addition, flower clusters heavy with water are more likely to bend and break or to become mildewed.

The best way to water is with a soaker hose. The water slowly oozes from the hose's many tiny holes for several hours -- even overnight. All of the water soaks directly on the soil and down to the plant roots without any waste or damage.

Lay a soaker hose in place when plants are small and leave it there for the season.
© 2006 Publications International, Ltd.
Lay a soaker hose in place when plants are small and leave it there for the season.

Drip irrigation is another excellent slow-soaking system, but it's more expensive than a soaker hose. Thus it's probably a sensible alternative for those who have large plant beds or who garden in climates where irrigation is constantly needed in order for cultivated plants to survive. Once the system is laid out, it can remain in place year after year; in areas that freeze, however, it must be drained for the winter.

There are two additional factors that will help conserve moisture and thus reduce the frequency of need for watering. One is the incorporation of compost into the planting area; this causes the soil to be able to soak up and hold water longer. (This is true when organic matter is added to light and sandy soils; conversely, when it's added to heavy soils, it helps to lighten and aerate them.)

The second technique that helps retain moisture is the use of mulch. Laid on the soil surface between the plants, mulch protects the soil from sun and wind drying.

By using these two ideas, you can cut down on the time needed to care for your garden, and even more importantly, help conserve water, nature's precious resource.