Many annuals and perennials love full sun, but often the spaces in our gardens that get a lot of sun also tend to dry out quickly. Next comes a heavy rain and the top soil and plants get washed away. An excellent cure for this situation is ground cover. Most ground covers have dense, short foliage and shallow, tenacious roots that hold moisture and soil in place.
Many herbs work well as ground covers and are also healthy, delicious additions to soups, salads, stews and sauces. Creeping Thyme, Lemon Thyme and Wooly Thyme do an excellent job of covering and holding the soil and also shade the roots of larger plants, so keep them moist and secure. Thyme also repels many insect pests and makes great companion plants for perennial and annual flowers. Many nurseries sell little six-packs of thyme which you plant six inches apart to create a border. Also plant seeds among the baby plants to fill in a larger area more economically. Thyme grows from six to twelve inches tall and is hardy in zones 5-9. It prefers having its roots slightly shaded and the foliage in full sun, which makes it perfect for a border planting, and especially nice spilling over the rocks of a rock garden.
Creeping Oregano is another good herb choice for hot, dry areas. It grows much the same way as thyme, so you can mix and match them if you like. Oregano is an excellent herb used in Italian cooking.
Chives create a nice contrast to thyme and oregano as the grass-like reedy foliage is attractive when mixed with the small round leaves of thyme and oregano. Garlic Chives are attractive and delicious in salads, dips, and as a garnish. They produce pinkish-lavender round puffs of flowers in late summer. Their dark-green grassy effect make them an excellent choice for a sunny border. They don't like being totally dried out for too long, but do well in short dry spells.
SEDUM
Sedums are an excellent choice if you have light sandy soil or sandy loam that washes away in heavy rains. There are several varieties such as Dragon's Blood with short succulent foliage that is a deep reddish-purple. Blue Spruce sedum is a pretty deep bluish-green foliage and is pretty when planted with yellow varieties. They love hot dry weather, yet soak up a lot of water when it rains. Sedums are used on 'green roofs' that replace old shingle roofing with plantings that are great for the planet as they soak up a lot of runoff water and clean the air. We have it next to our garage where nothing much grows in the sandy rocky soil. Sedum is great for crowding out weeds and grass that comes its way and forms a dense, low carpet that has tiny blooms in late summer. It is quite cold hardy, up to zone four or five. It spreads by roots and reseeds itself, so once it's established it requires no attention for a long, long time. Sedum is hardy zone 5-9 and prefers full sun and grows best in sandy or light loamy soil...
CACTUS
Believe it or not there is a cactus that is cold hardy to zone 4! Prickly Pear - Growing the Hardy Cactus Opuntia compressa - Eastern Prickly Pear will quickly fill in a large area if given full sun. A friend gave me one small piece of it when I complained that my cat was using my succulent bed for a potty. The spiny cactus quickly deterred the puss from the flower bed and took over, too! It has flat green pads and pretty yellow flowers in early summer. This is an excellent choice for hot, dry slopes where nothing will grow. Be mindful that they have long, sharp spines as well as short tiny pickers that are difficult to remove from your skin. I use kitchen tongs when handling it. It's very easy to plant, simply rough up the soil and toss on top! Try several small clumps of various ground covers to see which ones work best in your garden and discover the shapes and colors you prefer
ANNUALS
If you'd like more color; petunias, portulaca and alyssum are good temporary ground cover and are excellent to plant between small clumps of perennial ground cover until it fills the area you'd like to cover.
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