When to Water

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When watering the vegetable plot it is worth ensuring that one gets maximum benefit from the water applied.

When using can or hand held hose, water individual plants thoroughly, rather than watering whole area. For plants which need regular water, sink a pot plant down to soil level (say 12cm) next to these plants and water into it. This takes water straight down into the soil where it is needed and stops soil being washed away from around plant.

If using a sprinkler, a good soak once in a while is far more beneficial then a little and often. Check the soil after you have watered to see how deeply the water has penetrated.  It can be surprising the amount needed to make any real impression on a dry soil. Do not over water with a sprinkler as the action of water droplets can damage the surface structure unless it is rich in organic matter. Drip irrigation, which comes in various forms of leaking hose pipe, is much kinder to the soil structure and is much less wasteful.

Seedlings and young transplants should never go short of water but once established their need can vary considerably.

BROCCOLI, BRUSSELS SPROUTS, KALE: Once established if widely spaced these crops should survive without watering.

CABBAGE: If soil is dry, a watering of 22 litres/sq m two weeks before harvesting will give best value. Don’t overhead water or heads will split.

CAULIFLOWER: Lack of water in early stages can cause small, premature curds.

CELERY, CELERIAC, FLORENCE FENNEL: A good supply regularly otherwise they will be tough or bolt prematurely.

CHINESE CABBAGE: Needs a large and regular supply of water. Not advisable in dry areas.

CITRUS: Need heavy watering once a week.

FRUIT TREES (FLOWERING): Need heavy watering once a week.

LETTUCE: Water well, especially seven to ten days before harvest.

MARROWS, ETC: Unlike other fruiting crops, watering the growing plants encourages rather than reduces the crop. For maximum cropping keep moist from start to finish, increasing water as cropping starts. Try not to overhead water if subject to mildew.

ONIONS: Too much water delays maturity and reduces keeping quality. Only water in very dry conditions while plants are establishing.

PEAS and BEANS: In early stages don’t water unless soil is very dry as this encourages lush growth and delays cropping. Watering when plants begin to flower and pods are swelling will increase the crop.

ROOT CROPS: General watering. Only water when soil is drying out. Too much water will encourage leaf growth at the expense of roots. Water shortage: roots will survive better than most crops in drought. Try not to let soil dry out completely, or roots will tend to split when water is finally applied.

SPINACH: will rapidly run to seed in dry conditions. Silver beet more tolerant of dry conditions and NZ spinach quite resistant to drought.

STRAWBERRIES: Keep picked, mulched and watered. Mark good producers for new plants for next season and remove plants with mildew or rust.

TOMATOES: Once established do not water until flowering starts. Less watering will reduce number and size of fruit but these should be tastier. Try not to allow to dry out completely, once fruit set.

TOMATOES, EGGPLANTS & CAPSICUM, SWEET POTATO & CLIMBING BEANS: Will hold their blossoms and keep producing if soil is cool.

The above article is reproduced from the November 1989 COGS Newsletter and was developed from information supplied by the Henry Doubleday Research Association. The following additional information should be borne in mind:

  • Well composted soil holds water better and doesn’t dry out as quickly as unimproved soil.
  • When the soil has warmed up, mulching will also improve the water holding capacity of soils.
  • Tree roots will tend to “follow” water so don’t start your vegetable patch too close to large trees.
  • Remember that Australia is a very hot dry country, so in addition to the advice in this article, follow your commonsense and observe the health of your plants.