Growli

Fertilising guide

How to fertilise Wild Rocket (Diplotaxis tenuifolia)— schedule & NPK

Also called Perennial wall-rocket, Lincoln weed, Sand rocket.

More about wild rocket

About Wild Rocket

Diplotaxis tenuifolia · also called Perennial wall-rocket, Lincoln weed · edible

Wild Rocket is a perennial Mediterranean leaf vegetable with a more intense, peppery flavour than cultivated rocket. Unlike annual salad rocket, it regrows vigorously after cutting. Drought-tolerant and long-lived once established, it thrives in well-drained soil and full sun. Fully edible and pet-safe for dogs and cats.

Growth habit: Upright, multi-stemmed perennial subshrub

What fertiliser wild rocket actually wants — and why

Wild Rocket is grown entirely for its leaves, so nitrogen is the priority — steady, nitrogen-leaning feeding keeps it growing fast, tender and unbolted.

A nitrogen-leaning feed (higher first number) or compost-rich soil — nitrogen drives the fast, tender leafy growth this crop is grown for. Phosphorus and potassium matter far less here than for fruiting crops.

For the language behind the three numbers on the bottle — what nitrogen, phosphorus and potassium each do — see the NPK ratio explained entry. The short version for wild rocket: match the feed to the job the plant is doing right now, not to a generic “plant food” on the shelf.

How often to feed wild rocket, and which months

Feeding only earns its keep while the plant is in active growth and can use the nutrients — pour feed into a dormant or low-light plant and it simply builds up as root-burning salt. For wild rocket:

Wild rocket rarely needs feeding in the ground. In containers, apply a balanced liquid feed at half-strength once a month during the growing season (spring to autumn). Over-fertilising with nitrogen dilutes the characteristic peppery flavour. In practice: a balanced or compost-rich start, then a nitrogen side-dress or liquid feed every 3-4 weeks through the cropping period in the main season (spring through early autumn).

The dormant-season rule matters more than the exact interval: skip feeding entirely when wild rocket is resting. For the wider context on indoor feeding rhythms across the seasons, the houseplant fertiliser schedule walks through the year month by month.

What strength to mix for wild rocket

Use the vegetable-feed label rate for wild rocket. Steady availability matters more than a strong dose — a check in growth makes leaves tough and can trigger bolting.

Feeding always goes onto already-damp soil, never dry roots — water wild rocket first if the soil is dry, then apply the diluted feed. The companion question is when to water at all, covered in the wild rocket watering schedule.

Signs you are over-feeding wild rocket

Over-feeding is far more common — and more damaging — than under-feeding for most plants. The classic tells for wild rocket:

Signs you are under-feeding wild rocket

If the symptoms point at watering, light or roots rather than nutrition, the full wild rocket care brief covers soil, humidity and the common problems for this species.

Flushing and leaching the salts

For container-grown wild rocket, water until it drains freely each time and flush pots monthly with plain water to stop nitrogen salts accumulating; in the ground, good compost levels naturally buffer this.

Organic vs synthetic feeds for wild rocket

Organic options

Well-rotted manure or compost dug in, plus nitrogen-rich liquid feeds like diluted chicken-manure pellets or nettle feed. UK: pelleted chicken manure or Westland; US: Espoma Garden-tone or blood meal. Steady and soil-building.

Synthetic / liquid feeds

A balanced feed at planting then a high-nitrogen liquid or granular side-dress — UK: Growmore then a nitrogen feed or Phostrogen; US: a 10-10-10 then a high-N (e.g. 21-0-0) side-dress or Miracle-Gro.

Brand names are examples, not endorsements, and UK and US ranges differ — check the label’s own NPK and dilution rate, since formulations change.

Fertilising wild rocket — frequently asked questions

What fertiliser does wild rocket need?

A nitrogen-leaning feed (higher first number) or compost-rich soil — nitrogen drives the fast, tender leafy growth this crop is grown for. Phosphorus and potassium matter far less here than for fruiting crops. Wild Rocket is grown entirely for its leaves, so nitrogen is the priority — steady, nitrogen-leaning feeding keeps it growing fast, tender and unbolted.

How often should I feed wild rocket?

Wild rocket rarely needs feeding in the ground. In containers, apply a balanced liquid feed at half-strength once a month during the growing season (spring to autumn). Over-fertilising with nitrogen dilutes the characteristic peppery flavour. Wild rocket rarely needs feeding in the ground. In containers, apply a balanced liquid feed at half-strength once a month during the growing season (spring to autumn). Over-fertilising with nitrogen dilutes the characteristic peppery flavour. In practice: a balanced or compost-rich start, then a nitrogen side-dress or liquid feed every 3-4 weeks through the cropping period in the main season (spring through early autumn).

What strength of feed for wild rocket?

Use the vegetable-feed label rate for wild rocket. Steady availability matters more than a strong dose — a check in growth makes leaves tough and can trigger bolting.

What does over-feeding wild rocket look like?

Very soft, floppy, dark-green growth that attracts aphids. Excess leafy growth at the expense of hearts/heads in cabbage and the like. Salt crust and scorched leaf edges in containers; nitrate-heavy leaves. Letting wild rocket run short of nitrogen mid-crop is the main mistake — growth checks, leaves toughen and brassicas/leafy greens bolt or turn bitter. Keep nitrogen steadily available.

Should I flush the soil of wild rocket?

For container-grown wild rocket, water until it drains freely each time and flush pots monthly with plain water to stop nitrogen salts accumulating; in the ground, good compost levels naturally buffer this.

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