Plant Doctor Archive

Growing plants under mature trees

HELP! I have two oak trees which I cannot get anything to grow under. I have tried grass and several shrubs. I feel I am wasting my money but I wonder if azaleas or hebes may grow. Any advice welcomed.

Trying to get smaller or younger plants to establish under mature trees can be a long process. You have to remember that the trees have been there for a very long time, and over this period they have filled in large area with root mass, and during the day use up a lot of water and nutrients to feed themselves.

If you are going to have a garden bed under the oak trees, you will have to make sure that the hole is big enough to add some good compost to.

You may also like to add compost or potting mix to the surface to raise the ground level. Make sure that you feed the plants at the beginning with a good long-term fertiliser like Yates Magamp, and side dress each spring with Yates Professional Plant Food, Nutricote or Natures Way Bio Gold pellets.

If you want to feed weekly during the first couple of months, use Yates Nitrosol, Lush All Purpose or Thrive All Purpose. Make sure that the plants you are using are also suitable to the area - shady spot, appropriate size for the area and plants that will happily grow under established trees.

Clivias, liriope and agapanthus are all tough enough to cope with the situation.

Reproduced with permission from the former Weekend Gardener magazine. The views expressed here are not necessarily those of the RNZIH.