Watering Trees

Trees are a bit like umbrellas when it comes to rainfall – unless the ground is receptive (not surrounded by tarmac, concrete, pavement etc) the water runs off, not reaching the ‘ball’ of roots that use water best

Water when the tree comes into leaf (becomes ‘active‘) –  when the root system starts to draw in water.

Aim to keep the root-ball moist, but not sodden. Frequent ‘minor’ watering helps little as it causes roots to grow upwards to search for the surface water – not good.

Watering can capacity is usually 5 or 10 litres. You can use ‘grey’ water (from baths etc). Keep a record of how much water you think has reached the tree.

Newly-planted Trees

The roots of newly-planted trees are not able to seek out water until they are around three years old, so watering prevents drought. Water newly-planted trees during their first two seasons, during summer and when it is very dry.

Two full watering cans every other day throughout spring and summer is good.

Ideally, young trees should get 20 litres of water (in two doses of 10 litres twice a week) in March and April (total 40 litres/month) in their first year.

Once a week during the summer (May to August) give them 20 litres.
Give 40 litres in September – repeat if October is a dry month.

Even where there is a watering pipe, a rose attachment on a watering can can be just as effective in slowly spreading the water so as to saturate the entire root ball.:

Medium sized trees (10-12/14-16cm girth):

Spring and Autumn: 5-10 litres per week whilst leaves are visible
Summer: 10 litres per week. During long hot summers even mature trees can use extra water.

Here’s a rough guide to timing for young trees:

First Year after planting

MONTH Visits Visit frequency
MARCH 1 2nd week after planting
APRIL 2 1st and 3rd week
MAY 4 1 per week
JUNE 4 1 per week
JULY 4 1 per week
AUG 4 1 per week
SEPT 2 2nd & 4th week
OCT 1 2nd week if a dry month

Second Year after planting

MONTH Visits Visit frequency
MARCH 1 2nd week
APRIL 2 2nd week
MAY 2 1st & 3rd week
JUNE 2 1st & 3rd week
JULY 2 1st & 3rd week
AUG 2 1st & 3rd week
SEPT 1 2nd week
OCT 1 2nd week if a dry month

When planting a tree, the root ball should not be buried completely – leave it flush or even slightly proud of the surrounding soil level and cover with bark mulch.  This helps retain water and inhibit weed growth around the base of the tree.

Extremely hot weather – use ice!

Place big blocks of ice in the tree pit near but not touching the trunk and the water will efficiently percolate. You can make your own ice blocks by filling and freezing ice-cream tubs of water, having first eaten all the ice-cream 🙂

Feeding Trees

Mulching also helps retain moisture – bark chippings, leaf mould or well rotted horse manure area all good. N.B. fresh manure is too acidic – it can kill a tree. Make your own or buy products containing NPP (Nitrogen, Potassium & Phosphate) at garden centres, DIY stores or online.

To retain moisture and help suppress ‘competitive’ vegetation like weeds and grass, ‘mulch’ the area around the top of the tree pit with best quality bark chip mulch.

Care and maintenance

Check for broken branches. Those that extend over the roadside can suffer damage from parking and van drivers. Report damage to us.

If the tree has a metal tree guard, check that the rubber bands that secure the trees to the stakes are not too tight, or that they dig into the bark too much, and that they are doing their job of keeping the tree roughly upright and not letting it rub up against the cage when the wind blows.

Developments

Thanks to Peter for pointing out this article, based on research done by the University of Copenhagen, about the need to revisit how we grow street trees

Tools

  • Please contact us as any advice is gratefully received as to which ones are best.
  • A good quality pair of secateurs (and a leather holster). Secateurs are available both left-handed and right-handed. Search Ebay for ‘Secateurs’.

  • A pruning saw. Some come with holders that attach to your belt making them safer to carry when not in use. People with short legs may prefer one with a shorter blade as the larger holsters can uncomfortably jab in the back of the knees. Fine-bladed ones have smaller teeth which make a better quality cut but are a little harder to use. Consiuder getting a model for which replacement blades are available. Search eBay for ‘pruning saw’

pruning saw