Watering

Water requirements vary considerably based upon the type of plant, the soil mix that was used, the type of container, the amount of sun the garden will receive, and weather conditions.

Regardless of these factors, container gardens should be checked daily for water needs. Some plants, such as New Guniea Impatiens, drink a lot more water than others. These might require watering twice a day during the hottest parts of summer. Others, such as purslane or portulaca might require watering only once or twice a week, even in the hottest weather. The best method to check for soil moisture is the finger test. If the soil is dry, water deeply until excess water flows from the drain holes in the bottom of the container. Then wait until the soil dries out a bit before watering again.

Fertilization

Annual plants growing in containers will require more feeding than those grown in garden flower beds. Reason being is that they will have less soil to draw essential nutrients from and because more frequent watering will leach fertilizers from the soil mix.

Granular fertilizers. I like slow-release granular fertilizers best. These release a small amount of fertilizer every time the plant is watered. Some slow-release fertilizers last for an entire season while others might last a couple months or more. Check on product label for application rates.

Water soluble fertilizers. Soluble fertilizers can be applied weekly at one-fourth the recommended monthly rate. If the label calls for 1 tablespoon per gallon of water applied once a month, use 1/4 tablespoon per gallon of water and apply the solution weekly. Check on product label for application rates.

Maintenance

During the growing season, remove dried leaves and deadhead spent blooms regularly to promote continuous bloom and keep the plants more attractive. When trailing plants, such as petunias and verbenas, become long and leggy during summer you can cut the stems back to 6 inches or so in length to rejuvenate the plant and encourage more foliage and flowering. The plants should be back to blooming in just a week or two. After a cut back, fertilize and, if necessary, water well. Then resume normal watering.