Photo Photo Photo

Materials for sowing indigenous seedlings

Basic growing supplies required to grow indigenous seedlings include indigenous potting soil with a phosphorus count of 5 or less, slow release fertiliser, mulch - sand, fine gravel or vermiculite, tubes and tags for labelling. 

TreeProject volunteers will pick up growing supplies from the distribution point and date chosen on your Grower Registration Form. 

Indigenous Potting Soil 

It is very important to use appropriate potting mix to grow seedlings. Potting mixes are made from a range of materials (sand, peat, composted bark etc) that have been combined to provide the best growing medium for the plants. 

Indigenous seedlings are sensitive to an element in the soil called Phosphorus. Australian soils are often deficient in this mineral therefore many indigenous plants have evolved to compensate for this. 

Each potting mix is rated with an NPK ratio, Nitrogen for foliage, Phosphorus for nutrient interchange and plant processes, and Potassium for flower and fruit development. The majority of Australian plants require a Phosphorus count of 5 or less. 

Seedlings in soil from the garden will not thrive. Garden soil is fine in the ground but in pots it will compact and prevent the air and water reaching the plant roots so that starvation occurs. 


If the potting mix does not already have a slow release fertiliser in it indigenous plant fertiliser is required to boost the seedlings along. A 3 month slow release fertiliser is best. 

Make sure you mix the fertiliser evenly throughout your potting mix to ensure each tube has an equal mix of the fertiliser. This helps prevent the seedlings varying in size. 

After transplanting extra seedling into empty tubes, a seaweed based liquid fertiliser for indigenous seedlings can be used as a root stimulator to reduce shock and ensure seedling stabilisation. It is good practice to add this root stimulate again to the seedling a month before plating out on the land. 


The seedling tubes need to have a thin layer of mulch (sand, crushed gravel or vermiculite) placed on the top of the soil that serves as a mulch to prevent the seed from washing away and keep the spoil in the tubes from drying out.


A variety of sizes and types of seedling tubes are on the market. Most commonly used are forestry tubes. This size tube allow for 5-6 months of seedling development before being planted out. 

If your tubes have had seedlings grown in them previously ensure that they are sterilised in a weak bleach solution and scrubbed out with a brush to eliminate any contamination of pathogens lingering in the tubes. This is very important for preventing fungal diseases in the seedling you are about to sow! 

Tag Labelling

Tag LabellingEnsure that with each box of seedlings is a label with the species name, the sowing date. Do not rely on your memory to know when the tubes have been seeded and which species is in each box. Each species of seed has its own timeline for germination. Documenting the date that the seed is sown is crucial in order to track the seeds germination timeline.

It is important for TreeProject growers to include 4 bits of information on the labelling tag – (front of tag) species name, date sown, (back of tag) Your name and (who you are growing for) the Landholders name. The first two bits of information you will need to track your seedlings progress and report to you coordinator. The last two bit of information – Names – are crucial when the seedlings are delivered to the pickup point do differentiate you seedlings from the others that arrive.