Growing Succulent Borders

Soil

• Well-draining soil is basic to successful succulent gardening. Test drainage by digging a hole in the bed and filling it with water. If it doesn't all drain away within a few minutes, you need to amend the soil. Add organic matter, sand, gravel or pumice and dig it into the top 12 inches of soil. Alternatively, you can create a raised bed of well-draining soil for your border. Succulents generally are shallow-rooted, with roots near the soil surface so they can harvest water from even light rains. Some cacti send down deeper tap roots, but you don't need the depth of soil necessary for deep-rooted trees or shrubs.

Exposure

• Usually succulents grow well in full sunlight since most come from arid areas with high levels of sunlight. However, if you live in an area with hot, dry, sunny summers such as those in parts of U.S. Department of Agriculture plant hardiness zones 9 through 11, many leaf succulents do best in a location with morning sunlight and afternoon shade or partial shade. Assess the light conditions over the year in your border area to help plan placement of succulents. The amount of sun received will change with the angle of the sun and with shade cast by nearby buildings or tall plants.

Cold Tolerance

• Most succulents are hardy to USDA zones 9 and 10, so if you live within these zones you are practically unlimited in your choice of succulent plants. Many others also do well in USDA zones 8 through 11, although you might have to provide protection from cold, excessive heat and moisture. Some more tender plants hardy to USDA zones 10 through 11 include many aloes (Aloe spp.), Flaming Katie (Kalanchoe blossfeldiana) and other kalanchoes and many African crassulas (Crassula spp.). Low-growing succulents for USDA zones 3 through 8 include creeping sedums (Sedum spp.), some agaves (Agave spp.), prickly pears (Opuntia spp.), some hedgehog cacti (Echinocereus spp.) and hen and chicks (Sempervivum tectorum), with cold tolerance varying depending on the species.

Design

• Make a scale drawing of your border area to plan your design. Find out the mature size of your prospective succulents to determine how many of each kind of plant you'll need. Usually combining succulents of different heights, textures and colors lends richness to your border. Grouping three or more kinds of succulents to create natural-looking clumps or swathes of one kind of plant leads the eye through the border. Choose slower-growing succulents for easier maintenance. You can keep costs down by propagating plants yourself over time, since leafy succulents grow easily from cuttings.