Hedge planting—Some tips on getting it right

Hedge planting—Some tips on getting it right

At Central Landscapes we are asked some great questions by our customers looking to get the best out of their garden. This query arrived in our in-box from someone who felt the clay soil was getting the better of his hedge.

While Garden Mix is the right product to mix in with the soil, we tried to make sure his hedge would adapt to the clay, by suggesting improvements from the base of the hole to the top layer and beyond. Here is the reply from one of our Central Landscapes staff who attacks clay with gusto:

Hi there,

As compost and bark are the ingredients in Garden Mix, these elements will already be doing some of the work, but you might need to use some gypsum and change your planting technique:

Questions to ask yourself:

  • Under the Garden Mix is it heavily compacted clay?
  • When you tip water into a hole does it drain quickly?
  • If you’ve already had a problem with a hedge in this area, are you using the wrong plant?

In my recent and ongoing experience planting hedges of three different varieties in heavy clay, I did the following prep as I planted - which has been very successful:

I dug the hole in the clay and sprinkled one third of a cup (handful) of gypsum into the bottom. I then placed a bit of Garden Mix and clay (broken up a bit) over the gypsum and placed the plant on top.

Filling in the hole around the plant was a mixture of clay and layers of Garden Mix, all firmed down. The reason I leave some clay is that there are nutrients in clay that are unlocked when it breaks down - as it does when worked in with Garden Mix. And straight Garden Mix on its own might create a sump if the base is hard clay.

In some of my worst clay areas I also incorporated handfuls of a compost mixed with worm castings called Grow-all. Most of our yards sell it by the bag. Mulch was applied on top because it evenly disperses water when it rains, rather than water just concentrating in the hole. While I leave a ‘collar’ around the stems of plants, I build up quite a layer of mulch around each plant.

I liquid feed absolutely everything I plant with Aquaticus Garden Booster. It is full of goodies and has an odour but the smell is gone by the next day and it’s amazing for conditioning soil.

Gypsum Claybreaker Aquaticus Garden Booster
I also liquid feed the new hedges every six weeks or so over the first year. People who visit ask why the plants are growing so well in the clay and I think it’s both the attention to planting and the liquid feeding. Trimming hedges late spring and again now keeps them bushy and thick as they grow.

I hope this helps. If the holes are not draining well, you could dig a trench to encourage the water to drain away.

And the trickiest plant of all in clay that is sometimes wet and other times dry is griselinia. It won’t be happy in wet feet. If you were planning a griselinia hedge then I advise you to use Plantmate (a sachet sold by good garden centres) which will attack the root rot disease that eats griselinia roots.

We are very happy to help with further advice.

We’re always amazed by the care and thought our customers put into their gardens and we really appreciate the opportunity to help out with good advice and great products.