If you have any wildflowers in your yard (in spite of almost no rain this winter), prolong their bloom period. Dig your finger down into the soil. If dry at 1 or 2 inches, apply water.
Finish Transplanting Landscape Plants
Dig those final holes and get trees, shrubs, vines, ground covers, cacti, succulents, and perennials into the ground. The goal is to let their roots establish before the intense heat of summer hits. Keep soil consistently moist for several weeks as roots acclimate, and then gradually taper off the time between irrigations. As a guideline in spring, water every three to four days for the first two weeks, then every six to seven days for the next two weeks. If the weather is hot, increase these frequencies.
Fertilize citrus trees with their second feeding of the year in April or May. Apply one-third of the tree's annual nitrogen requirements. Apply fertilizer at the outer edge of the canopy dripline, and water deeply. Water should soak 3 feet deep for mature trees; somewhat less for new transplants.
Water Containers Effectively
Containers need more frequent watering than plants in the ground as their roots can't expand into the surrounding soil to absorb water. How often to apply depends on the type of plant and the weather. As temperatures warm in spring, vegetable and flower containers in full sun generally need watering two to four times per week.
Water Tomatoes and Peppers
Maintain consistent soil moisture for tomatoes and peppers. Water to a depth of 12 inches. Apply a thick layer of compost mulch to retain soil moisture.