Gardening with Annuals

The vibrant colors of flowering annuals, lined up in containers, pots and packs at the nursery, tempt us each spring and fall. Each variety of these bedding plants, as they are called, looks appealing and we want to take all of them home to add to our gardens. But it’s a good idea to design and prepare planting beds before purchasing plants. Keep in mind that most annuals are high-water-use plants. For this reason, it’s a good idea to use them in up-close areas near patios or entries. Annuals are also excellent in containers.

Getting Ready to Plant

Planting at the right season can be the difference between success or failure. Ideal times to plant winter- and spring-blooming annuals are when night air temperatures range between 40°F to 60°F, and daytime air temperatures are 60°F to 80°F. Daytime soil temperatures should be about 75°F. These conditions generally occur from mid-October through November.

Add organic soil additives to planting beds and mix thoroughly to 6 inches deep. Do this several weeks before planting. Bypass this step for desert natives. Moisten beds to 12 inches deep.

New plantings can quickly become stressed if winds are strong or temperatures rise suddenly. Be aware of the weather and water new plants carefully. In fast-draining, sandy soil, moisture must be supplied regularly for plants to grow and remain healthy. Neglect will cause hardening of tissues and loss of plant health or life. Check the soil often to determine if plants need water.

Soil-borne organisms have plagued new plantings of petunias and vincas when they have been planted in the same location, year after year. Prevent by removing leaf debris from planting beds, discard dead or dying plants and keep plants growing vigorously at all times. Rotate plantings—don’t always grow the same kind of plant in the same bed. Try something new each planting season. Contact your nursery for current disease controls.

Planting Wildflowers

Many wildflowers are included in the Annuals charts. Including wildflowers in your landscape takes a little planning, but is worth the effort. Follow these few simple guidelines for preparation and planting.

In order of preference, fall, winter and early spring are suitable for sowing seed of spring-blooming species. Plant summer-flowering varieties during the spring.

Almost any sunny location (at least six hours of sun each day) is a candidate for wildflowers. Wildflowers native to the desert are, by their nature, better equipped to cope with our climate and soil conditions than water-demanding species introduced from other regions. However, like other plants, even tough desert natives require regular moisture to germinate seeds and establish seedlings.

Wildflower mixes adapted to grow in the low desert are available for Coachella Valley gardeners. Individual species also work well. It is a matter of preference as to what effect you are looking for. If you create your own combination, select wildflowers that bloom at the same time. Consider planting them in separate beds to create distinct bands of colors. Over time, wildflower plantings take on their own character as plants reseed, spread and reseed some more.

Sow seeds for spring-blooming annuals in the fall. Seed mixtures typically contain six or more species to ensure a long season and a variety of color. A 1-ounce seed packet will cover approximately 500 square feet.

Prepare the planting area by removing weeds and debris prior to cultivation. Rake lightly to create a seed bed. Soak the soil slowly to moisten 8 to 12 inches deep.

Broadcast seeds with a hand-held fertilizer spreader or by hand. Most wildflower seeds are very small. Mixing with fine dry sand provides more even distribution, and allows you to see where seeds are being applied. Don’t plant seeds too deep. Most wildflowers do best with 1/8-inch coverage of soil, but read the seed package to be sure.

After seeding, rake soil lightly in a criss-cross pattern to cover seeds. Water lightly with a fine mist attachment on the hose. Avoid washing soil or applying so much water at one time that it creates gullies and runoff. Water seeded areas regularly until seedlings appear. After seeds sprout, apply water a couple of times each week, depending on moisture content of soil. Pull weeds as they appear.

Adding fertilizer is seldom necessary. Most desert wildflowers do well in soils having low fertility.

Germination periods vary considerably for different wildflowers, and are affected by soil and air temperatures. Some may sprout in two weeks, others take four to six weeks. Adequate deep moisture is essential.

After plants complete their flowering cycle and go to seed, cut them back to about 6 inches high. With some wildflower species, you can collect seeds for next year’s planting. Some seeds will have been eaten by birds or otherwise lost. To ensure another season of color, reseed with about half as much as the original planting in the fall. Note that spring seeding for summer annuals will require more moisture compared to fall-seeded plants. Perennial species will usually continue into the following year.