“Do I need to dig a trench?”
This is one question that keeps popping up each year, when hedge planting season rolls around. And the answer is – sometimes ! It depends on the soil, the site and the plant – and your time and resources. We’re happy to help out with a little extra advice as hedge planting season is here.
If you are hedge planting long lengths of native hedging, digging a trench probably isn’t realistic, but for shorter lengths of hedge you may wish to cultivate the soil to prepare it for planting, and a trench may be your preferred way of doing this – either with a rotovator or by digging. If so – a few words of advice –
Digging & Compact Soils
Be wary about doing this in heavy clay soils, however. Using any machinery in this manner carries a risk of ‘smearing’ the sides of the trench which destroys the soil structure so it becomes almost watertight and also makes it difficult for roots to penetrate. It could also create a ‘sump’, where water can collect around plant roots. One way of avoiding this is to fork the sides and base of a trench to loosen the soil further.
Preparing the Trench
By this point you should have loosened the soil, and dug out a trench of appropriate depth, which depends on what you’ll be planting (the trench should leave the top of the rootball exactly level with the surrounding soil). If you’re fortunate enough to have a well-drained, loamy soil (this includes some clay), well-rotted manure, leaf mould, and organic compost can be added in small quantities to the soil. This isn’t the case for heavy soils, however, in which case you want to avoid adding too much organic matter to the mix, it is better to use this as a mulch on top of the soil. Instead use John Innes No. 3, or a gritty compost to plant with.
If you are planting yew (Taxus baccata), don’t add organic matter, yew is susceptible to phytophthora – a fungus which can be found in organic matter.