How Much Water Does A New Hedge Need?

After a long Winter and a ‘Spring’ that has mostly consisted of a succession of biting cold winds interspersed with regular night frosts, we are finally starting to get some nicer weather. Its fair to say Spring is very late this year, here in Kent most of the trees have only just producing leaves in the last few days after many weeks in bud. We have flowering cherries in full flow just now, in recent years the flowers would have dropped by now.

This is the time of year when hedges that have been planted over the last 6-8 months should be starting to come out of their Winter dormancy, making new buds and leaves. Don’t be too concerned if they seem a little slow to get going, new hedges almost always come into growth a bit later than established ones because they need to settle their new root system first. You can see this in our 2 batches of Green Beech plants growing on the nursery.

As your new plants start to grow its very important to water them, (especially bare root hedging plants) the new growth is particularly vulnerable at this time and may quickly wither and die off when the weather warms up properly if the soil is too dry. We usually get some nice rain showers at this time of year but Spring and summer rain alone is very unlikely to be enough to sustain healthy new growth, it waters the surface but doesn’t get down to the developing root system. To keep your new hedge growing well, check out our tips from Morris, our resident horticulturalist.

Do – water thoroughly. Give your new hedges and plants a thorough soaking. New bare root plants should have 5-10 litres of water once or twice a week (depending on the weather) for each metre of hedge. Root ball hedging plants will often need much more – up to 120/150cm in height would need 10 litres for each plant once a week, over 120/150cm 20 litres per plant once a week. If the weather turns very hot (we can hope) then twice weekly watering would be a good idea until the heat subsides.

Do – add a mulch (a layer of organic matter) around your plants if you haven’t already. Options include bark chips, well rotted garden compost, Coir mulch or even lawn mowings (provided you haven’t treated your lawn with weed and feed). This will act as a moisture retaining blanket around the base of your new hedge keeping the roots cool and discouraging competitive weeds. This is a great help on lighter soils that don’t retain moisture, on heavier soils it stops the surface from cracking too. For best results give your new hedge a thorough soak and apply the mulch afterwards. (Mulching is ideal for most species apart from Lavenders, Yews should be mulched with caution on heavy clay soils where too much moisture can be retained) To be really effective your mulch should be 5-8cm deep and at least 40cm wide along the length of your new hedge. Mulched hedges grow much faster and consistently demonstrate a higher success rate

Don’t – let weeds and grass to grow around your new hedge. Weeds and grass will always grow faster than your new hedge stealing vital moisture and light in the process. Even close mown grass will compete for moisture. Keep a weed free strip of at least 40cm along the length of your hedge.

Don’t – water every day. Little and often watering over time will encourage the hedge to root close to the surface for its daily ‘fix’ of H2O. The plants may look lush and healthy, but if you stop watering they will be very vulnerable to dry spells. Give them a good soak once a week, that way the roots need to search and establish more strongly in between waterings making for a stronger and more resilient hedge.

Don’t – water the foliage. Direct your watering efforts to the base of the plants at soil level where it can soak down to the roots. Misting the young new foliage can cause the soft leaves to scorch in sunlight and much of the water will be lost to evaporation before it gets to the root system. If you do choose to give your plants a misting over the top, wait until evening when the sun is going down and the danger of scorching has passed.

As temperatures rise some evergreen hedging plants will often turn yellow and progressively shed their old leaves. The most common culprits are bare rooted and root ball Laurels but all evergreens have the potential to do this. A lack of water is the reason, you may be watering regularly by the book, and have even mulched them….but if the young roots aren’t sufficiently developed to absorb and sustain the plant, then shedding leaves is the plants way to save water and survive. This is a normal response, and all is not lost provided the stems are still green underneath the bark (scrape with your thumbnail to check if you aren’t sure) New growth will come within a couple of months, as the roots become settled then new growth will follow.

If you need any other tips on establishing your new hedge why not visit our How To Plant A Hedge page for the full details

About the Author

Morris Hankinson is the founder and MD of Hopes Grove Nurseries, the largest grower-retailer of hedging plants in the country. He started the business in July 1992, the day after completing his last exam of a BSc. Horticulture course at Writtle College in Essex. Morris has had a fascination and love of growing things since childhood when he was a keen exhibitor at his local Horticultural Society. Over the years the nursery has developed from a one person operation to an employer of 25 staff and so his interest is put to very good use, keeping an experienced eye on all operations across the 125 acres of nursery production.

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