Yes, soil preparation drought plants need focuses on one thing above all else: drainage. These plants evolved in rocky or sandy ground where water drains away fast after rain. They cannot survive in soil that holds water around their roots for days. Get the drainage right and your drought plants will thrive with almost no extra care from you.
Good drainage for xeriscape gardens makes the difference between plants that thrive and plants that rot. Water must move through your soil and away from roots within hours, not days. When your soil stays wet, roots cannot get the oxygen they need and start to decay. Most drought plant deaths come from drowning, not from thirst in the garden.
I learned this painful lesson with my first lavender plants in heavy clay soil several years ago. They looked great for two months after planting in spring when the weather stayed dry. Then the summer rains came and three of my five plants turned brown and died within weeks. The roots had rotted because my clay soil held water like a bathtub around them.
You should test your drainage before planting any drought plants in your yard. Dig a hole 18 by 18 inches (46 by 46 cm) wide and deep in your planting area. Fill it with water all the way to the top and watch how fast it drains. If the water goes away within 30 minutes, your soil has good drainage for drought plants.
Drought plants evolved in harsh rocky or sandy soils where nutrients run low but drainage stays high. Their roots spread wide rather than deep to catch rain before it drains away fast. When you put these plants in rich dense garden soil, they often grow too fast and become weak. They also suffer from root rot because your soil stays wet too long after rain.
Amending soil dry garden style means mixing the right materials into your clay to improve drainage. Add coarse sand and gravel to your clay to open up air spaces for water to drain through. Mix in some compost to reach the 4% to 6% organic matter level that works best. Avoid fine sand, which can make your clay even denser and harder to work with.
The well-drained soil requirements differ based on which drought plants you want to grow in your garden. Lavender needs the best drainage of all and often does better in poor rocky soil. Sedum tolerates a wider range of soils as long as your winter drainage stays good. Russian sage handles clay better than most once it gets established after a year or two.
Raised beds solve drainage problems when amending your native soil is too much work for you. Build your beds at least 8 inches (20 cm) high and fill them with a mix of native soil, sand, and compost. The extra height lets gravity pull water down and away from your plant roots after rain. This approach works great on slopes and in areas with heavy clay.
My second planting of lavender went into amended soil with plenty of sand mixed into the clay. I also added a 3 inch (8 cm) layer of gravel mulch around the plants to keep moisture away. Those plants are now five years old and bloom better each summer in my garden. Good soil prep made all the difference between failure and success for me.
Read the full article: Top 10 Drought Resistant Plants for Gardens
