Plant Soaps & Wetting Agents

Plant soaps & wetting agents

Make every spray work harder

A plant soap is a concentrated, potassium-based fatty acid soap made specifically for use on plants: biodegradable, free from added fragrances, dyes, thickeners or detergents, and safe to use as a regular hygienic plant wash. A wetting agent (also called a surfactant) lowers the surface tension of water so that sprays, drenches and watering penetrate evenly. The Dr Forest range is handcrafted in Stockport using organic ingredients including neem oil, mustard seed, soap nuts and aloe vera.

What's in the range

  • Bio-Plant Soap Concentrate: handcrafted potassium-based soap for hygienic leaf washing and as a wetting agent for foliar sprays.
  • Neem & Mustard Seed Plant Soap: made with organic neem oil and mustard seed for keeping foliage clean.
  • Natural Wetting Agent: a gentle surfactant made with organic soap nuts (saponins) and aloe vera. A few millilitres in your spray tank or watering can transforms how water and feeds behave.

What's a wetting agent for?

Three jobs in one bottle.

1. Foliar sprays. Water naturally beads up on plant leaves and rolls off, especially on glossy, waxy or hairy surfaces. A wetting agent breaks the surface tension so water (and anything dissolved in it) spreads into a thin, even film across the whole leaf. Add it to your foliar feeds, biostimulant sprays, leaf rinses and tonics. Every application works harder for the same volume sprayed.

2. Root drenches and liquid feeds. The same effect happens at the root zone. Adding a wetting agent to root drenches, biostimulants and liquid feeds helps the solution penetrate deeper and more evenly through the rootball and surrounding soil, so nutrients reach more of the root surface instead of channelling past.

3. Re-wetting very dry compost and potting mixes. Once peat-free composts and potting mixes dry out completely, they can become water-repellent: water rolls off the surface or runs straight through the pot without soaking in. Bark-based and peat-free mixes are particularly prone to this. A small dose of wetting agent in your watering can breaks that surface tension and lets the medium fully rehydrate, restoring water-holding capacity.

How to use plant soaps

Dilute as directed on each product page and apply with a fine-mist sprayer to clean dust, residues and grime from foliage. Soaps and surfactants in this range pair well with our liquid fertilisers and biostimulants: a small dose in your spray tank improves coverage and consistency.

Plant soaps & wetting agents: common questions

On most, yes. Always test on a small leaf area first. Some sensitive plants (ferns, succulents, freshly transplanted seedlings) can react to surfactants.
Early morning or evening, out of direct sun. Avoid spraying in temperatures above 25°C or strong sunlight to prevent leaf scorch.
Yes. That's one of the main uses. It helps both foliar sprays and root drenches penetrate evenly. Check each product page for dilution rates.
Yes. Dry, water-repellent compost and potting mix is one of the main uses. A few millilitres of wetting agent in your watering can lets water soak in instead of running off the surface or straight through the pot.
Whenever they need it. Dust, residues or grime are good signs. Plants grown under cover, or near radiators or fan vents, tend to need it more often than those outdoors.