SeaFeed – Seaweed Liquid Fertiliser

*For best results from the new NZGA range, use SteadyGro as your base fertiliser across the garden, then rotate through the four liquid products weekly, applying them as either a soil drench or foliar spray.

SeaFeed is made from seaweed wild-harvested from New Zealand and cold-extracted without heat or chemicals. That extraction method matters because heat degrades the bioactive compounds, amino acids, and growth-promoting substances that make seaweed extracts genuinely useful. What you’re getting here is as close to the raw material as a liquid product allows.

Seaweed extract isn’t a primary fertiliser and SeaFeed doesn’t pretend to be. What it does carry is a meaningful mineral profile, particularly magnesium at 6,000 mg/L and boron at 21 mg/L, both of which are frequently deficient in NZ gardens and rarely addressed by standard NPK fertilisers. Calcium, sulphur, and iron round out the trace element content.

Beyond the minerals, seaweed is rich in natural compounds including amino acids, alginates, and plant hormones such as cytokinins and auxins. These improve root development, support cell function under stress, and help plants recover from heat, drought, frost, and disease pressure. They also stimulate soil microbial activity, which improves the availability of nutrients already in the ground.

The best way to use SeaFeed is as part of a broader programme. Pair it with a granular or higher-analysis liquid fertiliser for the NPK backbone, and use SeaFeed to top up trace minerals and condition plants through the growing season.

How to use

Garden beds, soil drench

Mix with water and apply to moist soil during active growth. Water in after application. Avoid applying in extreme heat or when the soil is very dry.

Foliar spray

Dilute and apply directly to foliage in the early morning or late afternoon. Particularly useful as a stress response treatment or to address suspected trace mineral deficiencies showing in leaf colour or growth. Avoid applying in hot conditions or when foliage is slow to dry.

Lawns

Apply through a watering can or sprayer and water in well. The magnesium and bioactive content can improve colour and recovery after stress periods such as drought or heavy wear.

Pot plants

Apply to moist potting mix at the rates below. Potted plants are more susceptible to trace mineral depletion, so regular light applications give better results than occasional heavy ones.

Frequency

Every 2 to 4 weeks during active growth. Can be used more frequently during periods of heat, drought, or visible plant stress.

Application rates

Garden beds (soil drench)
Apply 50–80 mL per 10 L of water, covering 10 m²

Foliar spray (all plants)
Mix 50–80 mL per 10 L of water and apply evenly to leaf coverage

Lawns
Apply 200–300 mL per 5 L of water per 100 m²

Pots & containers

Small pots (up to 15 cm): 3–5 mL per 1 L of water
Medium pots (20–25 cm): 5–10 mL per 1–2 L of water
Large pots (30–45 cm): 10–20 mL per 2–4 L of water