Gardening Tips and Guide
Most of the garden plants have an incredible ability to keep themselves cool. But it is extremely important to know how much water does the garden need.
Basically, moisture from the soil is taken in through the plant’s roots and pushed out through its leaves, creating an ongoing cooling effect (transpiration).
So long as there is adequate moisture in the soil, the leaves on a healthy sun-loving plant should not become scorched.
On a normal mild summer’s day, a well-grown tomato plant is likely to use four to six litres of water a day.
However, when temperatures spike, water use also spirals and the tomato plants may use 8-12 litres to avoid stress.
Similarly, a medium-sized fruit tree with an average crop, two to three weeks away from harvest, may use 100 to 300 litres of water a day under normal conditions but soak up double this amount under high heat.
Most determine their plants’ water needs on a time basis – sprinklers set to run for 20 minutes twice a week or drippers for two hours once a week.
However, it is far more efficient to identify how many litres different plants need on a daily or weekly basis.
The amount of moisture absorbed by a healthy plant can be two to four times greater than one struggling. In this case, the plant will use more water, but it will be in a much sounder position to keep itself cool.
When you water by time, it is important to realise the amount of water available from these systems varies considerably.
In this case, the time needed to water the tomato plant, referred to earlier, will vary dramatically.
The key to preventing heat stress during extended hot weather is to make sure there is plenty of moisture in the plant’s root system at all times.
In most situations, but not all, watering more often is far more efficient and effective than retaining your existing watering frequency but watering for a longer period.
The aim, when watering, should be to apply enough water to soak the plant’s root zone. If you water longer, much of the additional moisture will soak below the root system and be lost.
On the other hand, watering more often will return moisture to the root zone before reserves are depleted.
As a general rule, plants with a shallow root system – vegetables and flowers – need more frequent watering than those with a deep root system, such as large shrubs and trees.
After three or four days of above-average temperatures, soil moisture levels within the root zone will be very low and unless significant rain is forecast, it should be restored quickly.