Every year the Pacific slope and Central Valley of Costa Rica face four months of dry, hot weather, practically without rainfall. A blazing tropical sun can overheat exposed soils, endangering the biotic life in the topsoil. Earthworms, for example, retreat to the depths of the soil and remain there until the rains return.
Plants become dehydrated quickly in these dry conditions, and wilt rapidly without constant irrigation. Many folks just give up gardening this time of year; but even though these are difficult months, there are several things you can do to keep your garden green and productive.
First, cut your gardening activities back so you don’t overstretch yourself – or your water supply. Use a few beds with plenty of diversity. Closer spacing between plants will shade the soil below to slow evaporation and lower soil temperatures.
Mulching with grass clippings or dried leaves is one of the best water-conserving tricks a gardener can use. Your soil will stay moist and cool, permitting better root growth and greater worm activity in the bioactive zone.
Use 15 centimeters or more of fresh mulch on beds and walkways. In a short time, this will compact to a 5-7cm protective covering, giving your garden an attractive carpeted effect. Mulch is also a great cover for dormant planting beds; it keeps the ground moist and weed free, while worms stay busy aerating the soil.
As the rains return, this mulch can be incorporated into the soil to increase soil fertility. Water your garden in the late afternoon or evening.
This prevents excessive loss of water from evaporation by the sun. Watering in the evening helps more dew to condense on the garden during the night. Try to water the soil instead of plant foliage; more moisture will then be trapped in the soil under the mulch. Hand-watering with a garden hose equipped with a shower head is the simplest and most efficient method. If you really want to become a home garden ecologist, you can retrofit your plumbing so the water from the showers and sinks can be collected for watering.
Of course, you’ll need to switch over to biodegradable soaps, so the gray water is safe for plants, but this is a practice that really reduces your water bill and puts your home on the green list. As I mentioned in a previous article, try to design your home garden and landscaping with xeriscaping in mind.
The term derives from the Greek word, xeros, which means dry, and was coined in Denver, Colorado’s water department during the early ‘80s, quickly spreading to the southwest states, California and Florida. A xeriscape design consists of three important zones. The oasis zone is nearest to the house and should contain showy plants and the vegetable garden, which requires frequent irrigation.
The second zone is the drought-tolerant zone, where plants need an occasional watering during dry times. This area may consist of fruit trees and other ornamental plants that are drought resistant.
Next is the natural zone, which ideally needs no watering during the dry season. This area is usually away from the home with little traffic and visibility and should consist of totally native plants that weather the dry season without water. For example, the hardy local lawn grass called jenji brillo may turn brown during the dry season but never needs watering, and greens up as the rains return.
Experts say showy lawns use more water and require more maintenance than any other part of the home landscape. Shade cloth, or saran, as it’s known commercially, is another valuable addition to your summer garden. This helps tremendously to keep your garden cooler and lower evaporation rates.
A 50% shade mesh is the best for garden vegetables. However, a bamboo frame constructed over the garden and topped with palm fronds can substitute the costlier shade cloth.