Expert Tree Watering Tips

7 July 2025 2 minute read

Glamis Estate 220325 Saoirse Clohessy 46
Watering young trees is vital to ensure they fully take root in their new environment

Did you know that a tree needs water even after it's rained? Georgie Logan, our Senior Urban Forest Manager, explains when urban trees are in need of water, and how to water them.

What are the signs of an underwatered tree?

Here are some key visual indicators that a tree needs watering:

  • Brown/crispy or wilting leaves
  • Leaves are losing their normal green colour, turning pale/yellow
  • Crown dieback - dead branches at the top of the canopy
  • Sparse canopy with very few leaves
  • Dry, cracked soil around the base of trees

Why do young trees need watering the most?

Freshly planted young trees have small root systems relative to their canopy size. Since water is often stored quite deep in the soil, plants must send their roots just as deep to access this water. A newly planted tree can't do this yet, so we provide water to help it along.

Young trees also don't have much energy reserves to fall back on. Similar to camels in deserts that rely on fat reserves, trees store up energy in their roots, trunk, and branches - but it takes time to build those reserves, which is why regular watering early on is so important.

Tower Hamlets 180523 Saoirse Clohessy 70
Everyone can get stuck in with watering street trees!

How much water does a young tree need?

Industry recommendations are to water trees 'to field capacity', which essentially means water until the soil is saturated and is no longer draining away (but don't leave a big puddle!) We've found 50 litres a week to be a good amount for a newly planted tree.

Regular watering is almost more important than volume, so ten litres a day would be more beneficial than 50 litres in one go.

Why water even if it's been raining?

Often when it's been dry and hot, rain is not able to penetrate into the soil very well. Water will run off the hard soil and go down drains, or evaporate on hot, concrete surfaces. This is why watering devices such as tree bags and pipes are so helpful. Tree bags release water slowly, giving the soil time to absorb the water, and pipes penetrate deep into the more absorbent soil below. 

Victoria Park Bupa CVO 130625 Sol Denker 4
Our teams are out watering the 1,000+ standard-sized trees we've planted in London over the last 3 years

Support your local new trees

If you've got new trees on your street, take part in our #WateringWednesday initiative by giving them a drink every Wednesday during the summer months. Your local council will be watering the trees, but we can all do our part by providing additional water, ensuring these baby trees will grow to keep your street cool for many decades to come.

Additional reading

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