Shrubs in containers offer many rewards, but because their roots cannot explore the surrounding soils it is vital to ensure they are supplied with nutrients on an on-going basis. Depending on the type of shrub you are growing we suggest one of the following mixes, Debco Terracotta & Tub, PotMate Premium Mix, or Debco’s Gardenia, Camellia & Azalea Mix specifically formulated for acid loving shrubs.
It is not necessary to replace the potting mix every year. The top 50-75mm of mix can be removed, making sure you don't damage too many roots. Then top up again with one of the above suggested mixes.
In the third year, allow the mix to dry and carefully remove the shrub from the container by laying the container on its side and gradually pulling the shrub out. If growth has been effective it is likely that there will be a lot of fibrous root growth.
Some of this can be pruned away carefully without damaging the plant. With a small hand fork, drag out some of the mix from within the root ball.
Empty any mix remaining in the container and pour one of the suggested mixes into the container so that the shrub may be replanted at its original depth. Place the shrub back into the container, making sure it's straight, and pour new mix around it, packing it around the roots.
Before filling the container to the original level, soak the mix to remove air pockets in the container and then top up with the Terracotta & Tub, PotMate Premium Mixture or Gardenia-Camellia-Azalea Mix.
Prune the shrub as required to allow for future growth, removing any branches that have been damaged, any dead or diseased growth and giving a general trim.
The suggested mixes all contain a slow-release fertiliser, but it is worthwhile using Debco Plant Food in the early days to encourage short-term growth, including new root growth development.
If you wish to plant a seedling colour display beneath your shrub, do so now. Seedlings will benefit from on-going application of Debco Plant Food every two weeks to maintain effective growth.