Plant Nutrition


We as people need good nutrition to be at our physical best and to stop getting sick and the same applies to plants, without proper nutrition plants don’t grow very well. There are many ways to feed plants. Some nutrients occur naturally in the soil but different areas whether it be sandy near the coast or gravel rock in the hills, all soils are different. Fertiliser can be added to the ground where it is taken up by the roots or foliar feeding on the leaves.

We shall explain the many fertilisers you can use:

Animal Manures – Are organic from animal by-products i.e cow, sheep, pig, horse or chicken manures. We sell manures by the bag at Landsdale plants PA290529PA290530

Don’t use manure from dogs or cats, it may carry disease organisms.

Don’t put raw manure on gardens as its generally high in nitrogen and ammonia which can burn roots, if you do purchase raw manure from a farm let it rest for up to 6 weeks before planting anything. Raw manure can also be full of weeds.

The benefits of manure either dug into the garden or used as a mulch are enormous as its a waste product so its a good way of recycling. Manure improves soil structure, adds nutrients, holds moisture and improves micro-organisms activity. It may smell initially but within a few days it will disappear. Always use gloves when forking manures into soil.

Blood & Bone – can be purchased as a powder or liquid. Its made up of a dried mixture of blood, meat waste and bone dust and is suitable for all garden plants. Its rodent repelling. Dogs like to lick the bone meal remnant in the product so keep them away from it, it will do them no damage but they probably don’t need fertilising!  It is an excellent food for microbes in the soil, it helps them to multiply , increases their activity in the soil, stimulates earthworms which keeps the soil healthy. The bone meal contains calcium and phosphorus and the meat meal and blood is full of nitrogen which makes plants lush and leafy and its good for the environment.

Compost – Is decomposed matter that has rotted down and then can be forked back into the soil as a soil improver. Its usually brown or black and has an earthy smell. You can make it at home yourself by using old food scraps and adding newspaper, water, manure, twigs, branches, leaves and turning it over regularly in a pile or you can purchase a compost maker from a hardware store. It may take weeks or months to be ready for your garden. You can also buy it already made in bags from Nurseries,  Farms and Hardware shops. Always wear gloves when handling as there are live micro-organisms in the product.

In-Organic fertilizers – These can be granular, for example, like Osmocote or as a powder or liquid like Thrive. They contain chemical elements which may be lacking in the soil naturally but are needed for good plant growth. The container or bag should tell you which chemical ingredients are in it and the quantity of each present in the product. The most common used are Nitrogen, Phosphorous and Potassium. Nitrogen promotes strong, healthy leaf growth, Potassium commonly called Potash enhances and deepens flower colour and improves fruit quality. Phosphorous is responsible for the reproductive parts of the plant – the flowers, seeds and fruit, so if you want more fruit on your passionfruit you could apply phosporus to the ground. NPK Blue is a product which can be brought which has all of these ready to use as granules. They are usually slow release which are easily spread around the plant and watered in. After 3-6 months they will have dispersed and can be added again. Powdered forms are mixed with water in a watering can or sprayer and usually applied over the foliage for instant fertilizer and can be applied more regularly. Apply at recommended rate or you may kill your plants with kindness. Can be applied fortnightly at full strength or weekly at half strength. Don’t apply in the heat of the day. Water foliage first, then pour liquid fertiliser to the soil and/or foliage, then water over again. Apply when the plant is actively growing, flowering or fruiting. Especially useful for annuals which have a short life as they offer a quick response to correct nutrient deficiencies or give the plant a general boost. Common and popular liquid foods are Thrive, Powerfeed, Nitrosol and Miracle-Gro.

Trace Elements – Some nutrients are required in small quantities by plants and are called Trace Elements. They are still vital for growing healthy plants. Copper, Zinc, Manganese, Boron, Iron, Nickel, Molybdenum and Chlorine can be known as Trace Elements. You can purchase containers called Trace Elements at the Garden shop that can easily be applied to the soil which contain these ingredients all in one. Citrus trees need a tiny bit of boron, when boron is deficient premature fruit drop can occur. A sprinkling around the base of the tree of a trace element mixture containing boron will help. A lack of iron in Azaleas which is common can be corrected with Trace elements. Copper deficiency in WA soils is very common as we have alot of sandy soil.

Urea – Is a synthetic fertilizer that is high in Nitrogen which encourages leaf and stem growth, but too much of it can stop fruiting and cause leaf burn. It easily breaks down in the soil and is good to use in compost piles. Urine contains mostly urea. It enhances vegetable growth and used mainly on leafy veges and ornamental plants that have lush foiliage. Wet plants first with water before applying urea or it will burn. Used alot for greening lawns.

Fish or Seaweed Emulsion – By adding fish emulsion organic gardeners can improve soil quality and accelerate the growth of plants due to the added micro-nutrients. Can be used as an alternative or in conjunction with conventional fertilizers. Its made these days from sea fish usually from a fish cannery or fish processing centre. A natural fertilizer is made from fish parts not used for oil, food or feed purposes. The by-products are then dried and cooked down into a thick liquid fertilizer. Phosphoric acid is added to keep bacteria at bay. Seaweed may also be added. In liquid form it needs to be diluted with water then poured over or even sprayed onto foliage. It adds nitrogen, phosphorus and potassium to the soil, and can invigorate seedlings, flowers, shrubs, vegetables, fruit, trees and grass. Its popular to use on tomatoes and roses and can also be added to the compost pile. Due to its strong smell it can also keep insects at bay.

Worm castings – Worm castings are loaded with beneficial soil microbes and other organisms that will help restore life and health to soils and in turn plants. They are a great plant fertilizer. They are earthworm excretions left behind by worms after they finish digesting the organic matter they eat as part of their diet. They are rich in nitrogen and can be applied directly to the roots without burning. They also contain traces of magnesium, phosphates, calcium, potash and potassium. You can buy worm farms and make your own fertilizer at home.

  Worm Farm




Handy Hint – Use the water leftover from boiling or steaming vegies, once cooled, to water potted plants, as they will benefit from the nutrients.