Olive Trees in Australia – Garden & Pot Grown

Olive trees are a timeless symbol of longevity — but to grow strong, stay healthy, and produce fruit, they need the right nutrition. Whether you’re growing olives in the ground or in pots on a balcony, using the best fertiliser for olive trees is essential for leaf health, flowering, and long-term productivity.

In this guide, we’ll cover how to feed your olive trees properly, when to fertilise, and what nutrients matter most — with fertiliser options designed specifically for Australian soils and conditions.

What Fertiliser Do Olive Trees Need?

Olive trees are hardy, drought-tolerant plants that still benefit from regular feeding — especially in pots or nutrient-depleted soils. They prefer a balanced NPK fertiliser with extra potassium for flowering and fruiting, plus trace elements to maintain healthy foliage.

Balanced NPK: Look for a fertiliser with even or slightly higher potassium levels, such as 20-20-20
Micronutrients: Iron, magnesium, and boron are especially important for olive tree flowering and disease resistance.
Form: Liquid fertilisers are ideal for quick uptake, especially in pots. Controlled-release formulas are suitable for in-ground trees.

For consistent, reliable results, use Complete Grow’s All Purpose Liquid Fertiliser (NPK 20-20-20) for mature trees and at half strength for potted & young plants

When and How to Fertilise Olive Trees

Timing matters when it comes to olive tree nutrition. Feeding at the wrong time can reduce flowering or stress the tree — especially in pots.

Olive Tree Fertiliser Calendar (Australia)

Early Spring: Begin feeding as new growth appears. This encourages leaf and root development.
Late Spring to Early Summer: Continue feeding to support flower formation and fruit set.
Late Summer to Early Autumn: One final feed strengthens the tree before cooler months. Use a balanced formula for sustained energy.
Winter: Avoid fertilising while the tree is dormant.

How to Fertilise Olive Trees in Pots vs. Ground

In Pots: Feed every 2–3 weeks during the growing season using diluted liquid fertiliser like Complete Grow 16-4-14. Ensure the pot drains well, and flush monthly to prevent salt build-up.
In Ground: Apply fertiliser every 6–8 weeks around the tree’s drip line. Water it in deeply. Use Complete Grow NPK 20-20-20 for fast absorption and even results.

Feeding regularly keeps the canopy lush, supports better flowering, and improves fruit quality over time — especially in Australia’s dry or sandy soils.

Signs Your Olive Tree Needs Fertiliser (And How to Fix It)

Olive trees are resilient, but they will show visible signs if they’re lacking nutrients. Here’s what to look for and how to fix it using the right fertiliser:

1. Yellowing Leaves (Chlorosis)

This often indicates a lack of iron, magnesium, or nitrogen. Use a fertiliser that includes chelated trace elements like the ones found in Complete Grow products to restore leaf colour.

2. Poor Flowering or No Fruit

Olive trees need potassium and boron for flowering. Use Complete Grow NPK 20-20-20 from early spring to promote blooms and improve fruit set.

3. Sparse or Stunted Growth

A general lack of nitrogen can slow growth and reduce canopy density. Feed regularly with a balanced fertiliser and avoid under-watering during hot spells.

4. Leaf Tip Browning in Pots

Often caused by salt build-up from over-fertilising. Flush the soil with clean water monthly and use diluted liquid fertiliser like NPK 16-4-14 at the recommended rate.

A consistent feeding schedule using Complete Grow’s Australian-made fertilisers will keep your olive tree productive, healthy, and looking its best all year.