Soil Amendments

Perlite and vermiculite: what's the difference?

Perlite is expanded volcanic glass: light, white and porous. Mixed into soil or coco at 10 to 30 per cent it opens the mix so water drains and air reaches the roots. It is the usual fix for a heavy or waterlogged compost.

Vermiculite is expanded mica. It holds water and nutrients and releases them slowly, which makes it the better choice for seed sowing, cuttings and any mix that dries out too fast. Many growers use both: perlite for air, vermiculite for moisture. Both are sterile, neutral and never rot.

Feeding the soil

Biobizz Worm Humus is pure worm cast, rich in humic compounds and microbial life; add it to a mix at up to a fifth by volume. Biobizz Pre-Mix is a dry organic fertiliser blend worked into soil before planting so the mix feeds itself for weeks. Ecothrive Charge is insect frass, a gentle organic feed that also triggers the plant's own defences against pests.