Firstly any perennial weeds or grass should be removed before planting. The use of a systemic herbicide (containing glyphosate) will kill any weeds down to the roots. This is much easier to apply before any planting is carried out. A weed killer spray such as ‘Roundup’ requires a dry spell of at least 4 hours once applied to be sure to do its job. If the soil is heavily compacted, the ground should be turned over to loosen and aerate the soil. This will make it easier for the roots of the new hedge to establish. If you are planting closer together, then it normally easier to dig a trench rather than individual holes and this also ensures the soil all the way along the hedge (also where the roots will grow) will have been turned over and de-compacted. If you are spacing the plants further apart and digging individual holes. Make sure the holes are of a sufficient size to allow the roots to spread out. Check the size of the rootballs or pots on the plants you plan to use to work out the size of trench or holes required.
Quality Of Soil
If the soil into which the new hedge is to be planted is not very fertile, then the addition of a fair amount of new organic matter is generally a good idea. Suitable products include Top soil or Garden Compost. Bagged compost can be used but really only as an additive to the soil. Using bagged compost on its own could make the ground very wet in winter and dry in summer as most bagged composts contain peat which is better used as a potting compost rather than in the ground.
The best types of fertiliser to use for a new hedge are controlled release fertilisers. These are insoluble granular fertiliers that release nurtrients gradually into the soil (with a controlled release period such as 6 months) This type of fertiliser can be added in the Spring when the plants start to actively grow again and will feed the plants through the growing season. Fertilisers which are not controlled releasing including manure and those derived from manure, can (if applied too heavy) scorch the roots of the new plants and cause burning of the foliage. Bonemeal or Controlled release fertilisers such as Osmocote are suitable fertilisers for use during and after planting, please follow manufacturers recommended rates.
Planting can be carried out at any time of year for potted plants. With the exception of drought or very cold conditions. If the plant rootballs are dry it is easier to make sure they are thoroughly watered before planting. Remove the rootball from the pot and submerse the rootball in a big bucket of water. Once the air bubbles stop coming up the rootball should be wet through to the core. Ensure all plants are thoroughly watered before planting. Backfill the trench or holes to the correct level for planting (top of the rootball should be around an inch below finished ground level). Place the plants in the holes or trench at the correct spacing and backfill with the loose soil & any additives. Firm the soil around the plants to prevent dislodgement by wind and if using taller plants or trees, these may require staking.
Feeding / Fertilising
Feeding a young freshly planted hedge will encourage it to grow and will speed up the establishment to mature hedge height. However, if your soil is already reasonably fertile and has been successfully used for garden cultivation, then it is not essential to add supplemental feed to the plants. Once a hedge has reached its desired size, then adding feed at this time simply means more growth that has to be cut off. The ideal hedge would be one that requires little maintenance once it has reached its desired height.
Feeding a young hedge is best done through the growing season from Spring to Summer when the plants are actively taking in nutrients. We generally recommend avoiding anything that is not controlled / or slow releasing as these types of fertilisers can scorch the roots of your newly planted hedge that can’t take the nutrients in as fast as they are being released.
Mulching is the application of a layer of organic material applied on top of the soil around the plants. It serves several purposes. It will suppress the growth of weeds in the newly planted area. Weeds will compete with your new hedge for moisture and nutrients so must be controlled. It will also provide some nutrients to the plants and conserve moisture by preventing evaporation. Suitable materials include Garden Compost, Mushroom Compost, Bark Mulch or Chippings. These should be applied at 2 -3 inches deep to be effective. This can be carried out in the Spring when there is still plenty of moisture in the soil. If applying in the Summer then the area should be well watered beforehand.
Any newly planted plants are susceptible to drying out if not carefully watered. This is particularly important if the planting is carried out during Spring or Summer and in sandy soils where moisture retention is poor. The first essential watering is at planting time. If the plant root balls have been allowed to dry out then they should be soaked thoroughly before planting and then watered in well after planting.
Watering should then take place at regular intervals unless their has been sufficient rainfall that the soil is already moist. The new plants can take up to 2 years to develop sufficient root system in the soil to support themselves. Up until this point watering is vital to plant survival, establishment and growth. Different soils will require different frequencies of watering. Get to know your own soil and how quickly it dries out in warm dry weather. The soil around the plants wants to be moist, not saturated, as most plants dislike prolonged periods in wet soil.
The best way to test if your soil needs watering it to feel around the base of the plants. Scrape away a few inches of soil and feel if the soil is dry or moist. If it feels dry or is only slightly moist at the bottom then you should water. Each watering should be a thorough drenching, applied evenly from a hose, watering can or leaky pipe type irrigation system.