JULY 2025

Having been asked by several people about watering I thought it might make a good subject for this month’s Diary post. During these hot spells I imagine it is a subject on many people’s minds. I’ll cover the hows and best practise of watering later on, but first I want to start at the very beginning because good watering practise begins with good soil management. 

Start with good soil

A good soil should be like a sponge, with a mixture of small and large pores/ spaces between the crumbs and particles. The large particles will be filled with air, but the smaller spaces will fill with water. Imagine a fully soaked heavy sponge, with all excess water drained, a good soil is just like this and able to hold a large quantity of water. At this stage it is said to be at field capacity.

In winter it is useful for a soil, be it garden, woodland, agricultural, to hold a lot of water as this prevents flooding of rivers and roads, and wider damage. This stored water can then be used by plants and organisms when it’s drier.

The water absorbency of a soil will vary between types (clay, sand, silt etc.), but all soils can be made more absorbent by adding organic matter (compost, manure, leaves, chipped wood, etc.) This can be mixed into the soil or applied as a mulch/ covering. Organic matter helps to enrich and feed the soil, encouraging the growth of fungi, some of which will form symbiotic relationships with plants thereby increasing the surface area from which plants are able to take up water. 

Cover the soil

Water is readily evaporated from exposed soil so either mulch the soil around plants or plant closely so that the foliage of neighbouring plants interlock to keep roots and plant bases shaded and moist. 

Assess the site conditions

If you have a garden or garden areas that are very dry then rather than spending many hours watering choose plants that are suited to the conditions. Many plants are far better adapted to coping with a lack of water than too much water, and will often bounce back after dry periods, and then there are those that positively thrive in dry conditions.

When to water

Ideally you want any water applied to have the greatest amount of time to be taken up by the plants. Therefore the evening is a good time to water as the cooler hours of the night mean less water is lost. If this is inconvenient then early morning can also work well, and is preferable for any west-facing areas as these will stay warm for much longer in the evening.

Where to water

Aim for the soil as water is taken up through the roots of the plant. Watering the foliage does raise the humidity level around the plant and hence lower the rate of water loss. However it can lead to infections on the leaves, flowers or fruit, discolouration and also leaf scorch so usually best to water the soil. This is not always possible and we do use sprinkler systems in some of the beds to essentially water from above.

How often to water

This is very much a case of ‘how long is a piece of string?’

There are many variables to consider such as the climate, specific microclimate, and the type of plant. 

Pots and containers require lots of watering due to their artificial environment, and lack of soil water reserves. Well established trees and shrubs should require no watering as they will have enough roots and symbiotic partners to access resources.

Get to know your garden plants, those that require more water will soon show you in their body language, and remember to give these some mulch in the dormant period to help them next year. Trees and shrubs will take a lot of water from the soil so any herbaceous plants near these will likely benefit from some mulch. 

Don’t be too over zealous in your watering. Newly planted specimens should be given plenty of water to start and get them established, but it’s important to then begin reducing watering. Plants need a chance to build resilience and grow deeper roots. If you water them with each drooping leaf you’ll spend the rest of your existence watering them!

For more established beds you don’t need to water every day. In hot weather (30°C) you may get away with watering 2-3 times a week, but make sure they have a good soaking on each occasion. As the temperatures fall reduce the frequency of watering and allow the rains to do the work.

A quick note on lawns- leave them a little longer in hot weather (only 1-2cm extra) to create a more humid microclimate around the roots. Don’t worry if they go brown, grass is very resilient, with a little rain they’ll green up again. Once recovered or as the temperatures drop and rains arrive drop the mowing height again to keep formal lawn areas looking tidy.

Keep plants healthy

As a final point plants are much like humans, the healthier you are the more resilient you are to stress. Chronic stress can be wearing and debilitating, but short term stress can be invigorating and motivating.

Remove any dead, diseased, or damaged material and treat any infections.

Prune out excess shoots on overgrown plants to reduce water need and improve airflow, but keep the soil covered by mulching or packing the plants together.

In summary it is important to consider the overall health and condition of the plants, soil and environment when watering. With some forward planning and attention to the care of the plants and soil through the winter and spring much less watering need be done through the summer.