Try to keep the foliage dry during watering. If you must use an overhead sprinkler, use it early in the day so the foliage will be dry by nightfall, lessening the chance of disease. If you live in a very dry climate, or if you are concerned about conserving water, choose annuals that are drought tolerant. Try cleome , dusty miller , globe amaranth, petunias and zinnia . Mulching The addition of a two to three inch layer of mulch will make the bed more attractive, reduce weeds, and conserve soil moisture.
Organic mulches are best.
Try bark chips, pine needles, shredded leaves or peat moss. The following year the mulch can be incorporated into the soil and new mulch added on top, resulting in an improved soil. Weeding Weeding not only keeps the bed more attractive, but also eliminates possible hosts for insects and disease and allows the flowers to receive the full benefit of the available moisture and nutrients. Weed carefully when the annuals are young so as not to disturb the young roots. Pruning The amount of care required by annuals varies.