What is the best fertiliser for a Lilly Pilly?

Lilly Pillys are popular Australian natives that grow in a variety of conditions and soil types.

We are reader-supported and may receive a commission on purchases made through links on this page.

When determining the best fertiliser for your Lilly Pilly, there are various factors to consider. These include the fertility of your soil and the age of the plants.

You also want to consider whether you want to encourage lots of new growth and/or you want your plants to produce abundant fruit.

What nutrients are necessary for Lilly Pillies?

Like most Australian natives, Lilly Pillies need a supply of nitrogen for good, strong growth. This is especially useful for young plants that still have a lot of growing to do.

It’s also vital if you’ve given your Lilly Pilly a heavy prune in winter and want to encourage it to become bushier.

Lilly Pillies also benefit from some potassium that helps keep the plants healthy and aids in fruit ripening. This can be helpful if you want your plants to produce plenty of fruit that you can harvest for making jam. 

What about phosphorus?

You may have read that phosphorus is not good for Australian natives. However, this is not entirely the case for Lilly Pillies.

In small quantities, phosphorus can help these plants to establish strong root growth and can assist with flower and fruit formation.

The reason it’s said that Australian natives can’t tolerate phosphorus is that, in general, our soils are deficient in this nutrient. Therefore, our native plants have adapted over time to cope with the low level of phosphorus in our soils.

It’s also important to note that there needs to be a certain amount of iron in the soil so that plants can metabolise the available phosphorus.

How to choose the best fertiliser for a Lilly Pilly

If we take all of this information into consideration, a fertiliser that contains nitrogen, phosphorus, potassium, and trace elements including iron is perfect to use on Lilly Pillies.

The fertiliser that you choose should have a higher nitrogen content, a small amount of phosphorus, and a slightly larger amount of potassium. 

All fertilisers will have this breakdown somewhere on the pack and the same formula is used universally. It appears as a set of 3 numbers that relate to the N:P:K content of the product.

Here’s how to determine the nutrient content of most fertilisers:

  • N is for nitrogen. It’s the first number in the N:P:K formula.
  • P is for phosphorus. This is the middle number in the formula.
  • K is for potassium. As you can guess, this is the final number.

So, as an example of a good fertiliser breakdown for Lilly Pillies, you should look for numbers like 10:1:5 or 15:2:7.

These examples denote that the fertiliser contains higher concentrations of nitrogen, minute amounts of phosphorus, and a relatively decent amount of potassium.

Why do younger plants need more nutrients?

Young plants still have a lot of growth to do. Plus, they need to establish a good strong root system. Basically, it’s the root system that feeds the plant and helps to promote strong growth.

Therefore, if you’re just about to plant your Lilly Pilly, you want to give it the best start in life. Ideally, this would mean adding some matured compost or other organic material to the soil before planting. This could include products such as blood and bone, cow manure, or even Dynamic Lifter.

Essentially, these products not only add nutrients to the soil but also help to improve the structure so that the roots can get a good start. This is the case for both sandy soils and soils that have more clay content.

Therefore, if you add these to your soil before planting your Lilly Pilly, it won’t need any additional fertiliser until the following spring.

Lilly Pillies will also benefit from plenty of mulch (e.g. pea straw) when first planted.

RELATED: Lilly Pilly Scale, Leaves Curling, Yellow, or Black

How to fertilise an established Lilly Pilly?

Depending on the nutritional content in your soil, a well-established Lilly Pilly hedge will benefit from an application of fertiliser in spring, as it comes out of their winter dormancy.

For Lilly Pillies, a slow-release fertiliser is best because it allows the roots of the established plants to take up the nutrients when they need them.

This is especially important for native plants because you don’t want to overdose them with too much fertiliser all at once.

Photo of author

Annette Hird

Annette Hird has an Associate Diploma of Applied Science in Horticulture. She has worked in a variety of production nurseries, primarily as a propagator. She also had the responsibility of a large homestead garden that included lawn care, fruit trees, roses and many other ornamental plants. More recently, Annette has concentrated on improving the garden landscape of the homes that she has lived in and focused a lot of energy on growing edible plants as well. She now enjoys sharing her experience and knowledge with others by writing articles about all facets of gardening and growing plants.