11 garden-watering basics

Plants need moisture for steady, healthy growth. Wise watering practices will save water and still deliver necessary moisture in a timely manner.

Make a custom waterer for a specimen plant.

• Perforate a four-litre (one-gallon) milk jug with several tiny holes on the bottom and sides and bury it near the plant with its spout right at the soil level.
• When the jug is filled, the water will seep out slowly and keep the roots moist.

• Less moisture evaporates in the cool of the morning, and there should be ample time for the water to soak in before the sun rises high in the sky.

If you must water later in the day, do it early enough so that the leaves dry before nightfall, to discourage foliage diseases.

• Keep leaves dry as you water, if possible, by watering only the soil around the plants.

This is especially important for plants that are prone to fungal diseases, including roses, lilacs, phlox and squash.

Getting the leaves wet with overhead watering can encourage the spread of many mildew and leafspot diseases.

Plants often wilt in intense sun, but they may not need watering.

• To avoid possible overwatering, wait until the next morning.
• If the plants are still droopy, they definitely need water.

• When watering mature plants, water deeply but infrequently to deliver moisture deep into the plants' root zones — usually between 15 and 45 centimetres deep.

Deep watering also encourages deeper roots, which in turn need less water.

After 24 hours, 2.5 centimetres  of water penetrates 30 centimetres  in sandy soil but only 10 centimetres in clay.

Young plants have shallow roots, so they need more frequent, light watering than mature, deeply rooted plants.

• Be sure to water trees and shrubs all the way out to the drip line, not just near the trunk or base.

Most of the young roots are under the soil at the edges of the canopy.

• During dry, dusty weather, water both the roots and foliage of evergreen shrubs and vines.

The leaves will appreciate having dust and dirt washed away.

When potted plants wilt daily, they are probably pot-bound, so there's no room left in the containers for soil or water.

• Give them bigger pots and fresh potting soil into which you have incorporated water-holding gel crystals, and you'll find they stay happy far longer between waterings.

To water plants beyond the reach of your hose, make drip jugs or buckets.

• Use a nail or an ice pick to make two small holes 2.5 centimetres above the bottoms of plastic pails or milk jugs, then fill them with water.
• The water will slowly seep into the soil, but some will remain in the bottoms of the containers and provide enough weight to keep them from blowing away.

Too much water?

• In a site that has poor drainage, install a piece of perforated drainage pipe under the ground, making sure that it tilts in the direction you want the water to go.
• If you need to provide a place for the water to go, create a dry well by digging a hole at least one metre deep and 0.6 metres across.
• Fill it two-thirds full with stones, top them with coarse gravel and cover the top with soil.