How Do I Rejuvenate Overgrown Laurel Hedges?
Laurels are one of the most responsive species to the major surgery of hedge restoration. Even the most hopelessly overgrown hedges can be drastically reduced in size and the unpromising woody stems will sprout with new foliage.
The best time to cut the plants back is in early Spring, well before the hedge is coming into growth (but provided the weather is not cold and frosty, if it is then wait until conditions improve). Start by reducing the height using a taught string line to keep it level, the height can be reduced drastically by several metres if necessary (even taking the plants back to stumps) although the work can be split over a couple of seasons if you are cutting the height back by more than one third.
The sides may be cut back at the same time or you might choose to reduce one side at a time, it really depends on how sensitive you are to the temporary lack of privacy that will inevitably follow for 2 or 3 seasons if all the work is done at once. The sides may be cut back by as much as several metres if necessary taking care to remove any diseased and dead wood as you go and making sure all the large cuts are clean without any ragged edges that will encourage disease to enter.
Once the hedge has been cut back it’s a good idea to give it a good feed with a general fertiliser such as Growmore, if possible forking it into the top 5cm of the soil around the hedge followed up with a good thick mulch of wood chips or garden compost after watering the fertiliser in well.
New shoots should start to appear from the bare wood within a couple of months, any long whippy growths should be pinched at the tips to encourage bushiness. Depending on how comfortable you are with the amount of privacy the new growth offers, you may choose to cut the other half of the hedge back the following Spring or leave it another year. Either way it should be possible to fully rejuvenate an old hedge within 3 or 4 years.