Rhododendrons, Azaleas, and Camellias are among the most rewarding plants in any garden — but they do have one firm requirement: acid soil.
UNDERSTANDING ACID SOIL
These plants evolved in woodland conditions where decomposing leaf matter keeps the soil pH low (between 4.5 and 6.0). In neutral or alkaline soil, they cannot absorb iron and other nutrients, leading to yellowing leaves and poor growth.
Before planting, test your soil pH with an inexpensive kit from any garden center. If your soil reads above 6.5, you'll need to amend it.
PREPARING YOUR SITE
- Dig a hole twice the width of the root ball and no deeper than the root ball height.
- Mix your native soil with ericaceous (acid) compost at a 50/50 ratio.
- Avoid adding lime or mushroom compost — both will raise pH.
PLANTING
Set the plant so the top of the root ball sits just above soil level. These plants are prone to root rot if planted too deeply. Backfill with your amended mix, firm gently, and water in well.
ONGOING CARE
- Feed each spring with an ericaceous fertiliser.
- Mulch annually with pine bark or pine needle mulch to maintain acidity.
- Deadhead spent blooms by snapping them off cleanly — do not cut into the new growth forming beneath.
With the right soil preparation, these plants will reward you with spectacular spring colour for decades.