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How to Plant an Annuals Garden


Starting Your Own Bedding Plants

For those who want to have an almost instant show of annual bloom, boxed bedding plants are the answer. The main drawback to purchasing boxed bedding plants is the limited selection. There are many annuals that are unavailable from any commercial sources. A gardener who wants them will have to start them at home. Also, if large numbers of plants are needed, the cost of boxed plants can be prohibitive.

In these instances, or just for the pleasure of it, you may want to start your own bedding plants. It's quite possible for any gardener to succeed with only a small initial investment in equipment and supplies. Here's what you'll need:

  • Light: The most essential ingredient for successful seed starting is adequate light. It's possible to start seeds on the sill of a sun-filled window, but plants often stretch out toward the light source and become leggy. A three-sided white or silver reflector shield set up behind the plant trays will reflect light back onto the plants to help combat this problem.

    Where there is not enough light available naturally, an easy alternative is to raise seedlings under fluorescent grow lamps. To provide maximum light from all sides, surround the area under the lights with a white or silver-painted reflector. Plants grown under lights grow straight and sturdy, unlike those grown on a windowsill.
  • Heat: Along with light, another need is adequate heat. The bottom heat that warms the soil in which the seedlings are grown is very important. If the air temperature in the chosen growing area is colder than 70 degrees Fahrenheit, bottom heat can be supplied by a heating cable installed under the growing medium.

    Equipment for starting plants indoors.
    © 2006 Publications International, Ltd.
    Some of the supplies you'll need to start plants indoors include a fluorescent grow light,
    an automatic timer, reflectors, a heating cable, and a drip tray.

  • Water: Water is a third requirement for plant growth. A rimmed watering tray will allow the seed trays and young plants to be watered from the bottom. Top watering can batter plants down, as well as increase the possibility of fungus problems.

    The primary concern with bottom watering is overwatering. Water shouldn't continuously stand in the watering tray. Pour lukewarm water to a 1/4-inch depth into the tray. Leave it for five to ten minutes. At the end of that time, observe how much water is left in the tray. Also, roll a small pinch of the planting soil between thumb and finger to test for moisture. What you want is soil that feels wet with very little or no water remaining in the tray.Test the soil moisture once each day by rolling a small amount between your fingers. Water again when the soil feels more dry than wet. It's impossible to predict how many days will be needed between waterings. You'll be able to make a fairly accurate "guesstimate" of your own circumstances after a few weeks.
  • Soil: Planting soil for starting and growing young seedlings should be free of weeds and disease. Buy prepackaged seed-starting mixes or create your own. If you mix your own soil, you must sterilize it. This can be accomplished by sterilizing the planting mix.

    First, spread it in a thin layer on cookie sheets and bake at a low temperature (150 to 200 degrees Fahrenheit) until it is completely dried out. Next, cool the soil and mix the water back into it until it's moist. Finally, pour the soil into sterile containers, allowing it to settle for a day before planting the seeds. A simpler approach is to purchase a specially formulated plant starter mix made up of inert materials. Fill the sterile containers with this mix, firm or tamp it lightly with your fingers, then sow the seeds.
  • Containers: Seeds can be started in a variety of containers: milk or egg cartons with holes punched in their bottoms or low on their sides, plastic or wooden boxes, clay or plastic pots, peat pots, or special seed starter cubes and trays are all equally acceptable. Virtually anything that will hold soil and allow easy passage of water through drainage holes in the bottom will work.

    Containers designed to hold a single plant are the best choice for large plants, which tend to crowd each other out in six-packs; for plants that don't like to have their roots disturbed by transplanting; and for climbing vines. Most annuals do well in any container.
  • Seed Sowing: Seeds can be sown individually in single pots. Plant two seeds in each, removing the weaker of the two seedlings when they grow their first real leaves (the very first leaves to unfold from a new seedling are called the seed leaves; the second set of leaves is its
    first true leaves).

    When sowing a packet of seeds in a box or larger pot, they can either be broadcast over the surface in a scatter pattern or be planted in rows. If only a few plants of each kind are wanted, rows make more sense; when larger numbers of plants are desired, broadcasting is faster. If the seeds are very small, don't cover them with additional planting mix after sowing; medium to large seeds should have a layer of planting mix sprinkled on top. Lightly press the surface of the planting mix after sowing.
  • Label: Be sure to label each planting in some way. The system doesn't matter as long as you have one.
Once the seeds are sown, water the seed trays from the bottom until the mix feels moist. Allow excess water to drip out of the container bottom before placing the container in your growing setup.

If the seed packet indicates that the seeds germinate best in darkness, lay two sheets of newspaper over each seed tray for the first few days. Many annuals require light for germination. Inspect each seed tray closely every day. As soon as you see seedlings pushing through, remove the newspaper layer.

Germination time varies widely. Ideally, you should start the slower growers earlier than those that germinate rapidly in order to have them all at the same stage when planting time arrives. Study the descriptions of each plant to know when to get each of them started. Following are some additional tips to help your seedlings grow properly.

Damping off causes newly sprouted seedlings to fall over and die.
© 2006 Publications International, Ltd.
Damping off causes newly sprouted seedlings
to fall over and die.

  • Damping Off: Probably the worst enemy of successful seed starting is a problem known as "damping off." It strikes within two weeks of germination when seedlings are very young. When it hits, the plants simply lay down and die, usually in less than a day's time.

    Damping off is a fungus infection that can best be avoided by making certain that both the soil and containers in which seeds are planted are sterile. The seeds themselves can be lightly dusted with fungicide powder prior to planting as an additional precaution. Young seedlings should be looked at morning and evening to check for any sign of a problem. Even if only two or three plants have lain down, take the precaution of immediately spraying the plants with a fungicide or, if none is available, try a mild vinegar solution.
  • Food: Prepared starter mixes usually have plant nutrients in them that feed the seedlings. If you make your own homemade starter from milled sphagnum, vermiculite, or sterilized sand, you'll need to fertilize in some way. The easiest method is to add a soluble fertilizer at a very weak rate to the regular waterings.

  • Pricking: Other than those that were planted individually, all seedlings should be transplanted from the seed trays when the first true leaves appear. This first transplanting is usually referred to as "pricking." At this stage, seedlings should be planted into small individual peat pots, planting cubes, or partitioned growing boxes. They will remain in these containers until planting time.

    Fill the boxes with a good potting soil or commercial growing mix. To make your own soil, mix equal amounts of garden soil or sterilized potting soil, moistened peat moss, and perlite or coarse builder's sand. Gently lift out and separate the young plants, holding them by their seed leaves. Place the seedling in the new container so the soil line will be at the same level on the stem as it was in the seed tray. Gently firm the soil around the plant roots, bringing it to within 1/4 inch of the container rim. Water from the top with a weak fertilizer solution. Place these pricked-off plants back by the window or under grow lamps to continue their growth.

    Transplant seedlings from starter trays when they grow their first set of true leaves.
    © 2006 Publications International, Ltd.
    Transplant seedlings from starter trays when they grow their first set of true leaves.

  • Hardening Off: By this time, plants should be stocky and strong, but they will need some toughening up. This process is referred to as "hardening off." It'll keep the plants from suffering shock, or trauma, when they are planted outside.

    Carry the plants outdoors each day for a few hours, bringing them back inside overnight. Shade them with an old window screen to protect them from strong light and wind. Start with two or three hours, then increase the length of time they're outside by an additional hour each day. After a week, they can be outdoors all day, and only need to be brought in at night.
  • Planting Out: At this point, the plants are ready to plant out into the garden bed. Those in individual peat pots can be dropped into planting holes, the soil firmed around the pot, an earth dam formed around the stem to form a water-holding area, and a weak fertilizer solution poured in.

    Plants in multi-plant containers will need to be turned out of the container and separated before planting. Water the plants well before removing them. If the soil is moist, they'll slide out easily, subjecting the plants to less shock. Some roots are bound to be broken off in this process; pinching out the top growth on the plant will help keep the top and root areas in balance. This pinching will also encourage side shoots to push out, helping to form a fuller flowering plant.
  • Shading: If possible, do your transplanting on an overcast and still day to cut down on wilting. If you must plant on a sunny and/or windy day, cover the transplants with a protective shield for a day or two. There are commercial blankets made of a non-woven material that will do this and can also be used at night to protect against light frosts. A do-it-yourself way to provide shading is to form newspaper sheets into cones and place one over each plant, anchoring the edges with soil.

Although starting your own boxed plants takes a bit of time and effort, it can be a very enjoyable activity. Best of all, you can have as many plants as you want of exactly the species and varieties you prefer.

Sowing Seeds Outdoors

Plants to Start Outdoors
These plants will do well if you plant them as seeds in the garden bed:
  • Sweet alyssum*
  • Baby's breath
  • Blanket flower
  • Castor bean*
  • Coleus*
  • Cosmos*
  • Cup and saucer vine
  • Dahlia*
  • Forget-me-not
  • Four o'clock
  • Gazania
  • Love-in-a-mist
  • Ornamental grasses
  • Marigold*
  • Morning glory
  • Nasturtium
  • Nierembergia*
  • Ornamental corn, kale
  • Petunia Phlox*
  • California poppy
  • Horned poppy
  • Portulaca
  • Scabiosa
  • Sunflower
  • Zinnia*
*Those plants that might be started ahead indoors or bought as boxed bedding plants.

(Note: Some plants on this list also appear on the list of those that can be started ahead as boxed plants. Either option is acceptable.)

Sowing seeds directly into the garden is the simplest method
of growing annuals. For those who have neither the extra money nor the inclination to buy boxed plants, sowing directly into the garden in springtime is the answer. Once the ground is warm and the planting bed properly prepared, it's amazing how
quickly most annuals sprout and grow to the flowering stage.

There are some plants that grow better when planted directly in the garden rather than started ahead as boxed plants. For example, both Shirley poppies and zinnias experience difficulty surviving transplanting. You'll also find that trailing and vining plants can't be started very much ahead of planting out time or they become hopelessly entangled. As a result, most vines
don't gain enough of a head start to make the extra effort worthwhile.

There are several ways to approach direct seeding. For a somewhat structured but still informal cottage garden look, use a stick to mark out flowing sweeps on the prepared bed. Plant each sweep with a different kind of seed. If the garden is large enough to allow it, repeat the same variety in several sections. Place taller varieties toward the rear of the bed and the lower ones at the front. There is really no reason to precisely plan in advance where each kind will go.

Broadcast the seeds in each section and rake lightly, then briefly sprinkle a fine spray of water over the bed to settle the
oil a bit. When the young seedlings sprout, they'll need to be thinned to prevent overcrowding. When thinning, adjust the
pace you leave between the plants according to their growth characteristics: Tall upright-growing plants such as plumed cockscomb, bachelor's buttons, and larkspur can be left much loser together than wide-spreading plants such as sweet alyssum, petunias, cosmos, and baby's breath. Surplus seedlings can be discarded, passed on to friends, or moved to grow in planters or other garden areas.

For a more formal garden design, make a precise plan on paper beforehand. Then carefully copy the layout onto the prepared seedbed. With this approach, each preselected variety is planted a rows or clumps in the appointed order -- two or three seeds to cluster, spaced 4 to 12 inches apart depending on
their growth habits. When the plants are 1 to 2 inches tall, thin out all but the strongest one from each cluster. The resulting beds will have a neat, organized, well-planned look that will enhance any normally laid-out garden design.

Another approach to flower bed layout is simply to mark off mows the length of the bed and plant each one with a different annual favorite. By planting the tallest kind in the back row and increasingly shorter ones in each row in front of it, it's possible to effectively display all varieties. Take into account the width to which each type grows when spacing the rows. Maintenance of this garden is easy because you always work along straight rows.

To decide which design style to use, consider what is best suited to your own tastes and talents, as well as to the style of your house and the already existing garden.

Broadcasting Seeds
© 2006 Publications International, Ltd.
With a stick or rake handle, mark out abstract sweeps on the prepared bed.
Then broadcast a different variety of plant in each section.

With your garden bed design in hand and your plants purchased or grown, you're ready to start planting. See helpful tips on planting and caring for annuals in the next section.


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