If you live in a climate where rain is sparse in the summer, or if portions of your garden are located under overhangs, it makes sense to choose plants that will tolerate minimal watering. The plants will have a better chance of thriving and you will have a more carefree gardening experience. All plants require regular watering for their first one or two seasons, but many drought-resistant plants will do fine with little water in subsequent seasons.
Buddleia alternifolia, or fountain butterfly bush, is a deciduous shrub (meaning that it will lose its leaves in the winter) that often resembles a small tree, as it can reach up to 12 feet high or more. With its arching branches and small clusters of abundant purple flowers, buddleia makes a dramatic accent at the back of the flower border or at the far reaches of your property. Not only does buddleia tolerate dry weather, it also prefers dry, gravel-like soil.
Whether you choose a low-growing cotoneaster for ground cover or a taller shrub variety that will rise up to 20 feet at the back of your garden, cotoneaster is a good choice because it grows quickly and thrives with little or no maintenance. The Sunset Western Garden book claims that it produces more of its bright red berries when planted on dry slopes and in poor soil than if it is planted in the rich soil of a normal flower bed. Cotoneaster is available in both evergreen and deciduous varieties.
Any member of the juniper family does well in dry climates. In fact, junipers will develop root rot if their roots sit in soil that becomes water-logged. Varieties of this evergreen shrub come in sizes ranging from 1 to 8 feet in height, all with needle-like foliage. The tree is seldom used for home gardens, but the creeping varieties are frequently used as ground covers and the taller shrubs, especially those with blue-green shades, add variety and interest to any flower bed. Junipers that grow in column shapes are used as windbreaks.
English lavender, or lavandula spica, is the most widely planted of all lavender varieties. It grows from 3 to 4 feet tall, but there are also dwarf varieties that are only 8 inches to 1 foot tall. The scented flowers are often use in teas, shortbread and perfume sachets. Lavender works well in herb gardens or in flower beds with other plants that prefer sun as well as dry, fast-draining soil. The plants can grow up to 4 feet across, so give them plenty of room in your garden bed.