Fertilising guide

How to fertilise Popcorn (Zea mays var. everta 'Strawberry Popcorn')— schedule & NPK

Also called strawberry popcorn, ornamental popcorn.

More about popcorn

About Popcorn

Zea mays var. everta 'Strawberry Popcorn' · also called strawberry popcorn, ornamental popcorn · edible

Popcorn is a flint-type maize whose hard kernels burst when heated. 'Strawberry Popcorn' is a compact, ornamental variety with squat ruby-red cobs that double as decoration and snack. Grow like sweetcorn but leave cobs on the plant until fully ripe and dry, then cure further indoors before the kernels will pop reliably.

Growth habit: Upright annual grass; 'Strawberry Popcorn' is dwarf and bushy, bearing many small, rounded red cobs per plant.

What fertiliser popcorn actually wants — and why

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

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 popcorn: 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 popcorn, 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 popcorn:

Moderate feeder. A balanced base dressing plus a nitrogen side-dressing when knee-high is ample; avoid heavy late nitrogen, which keeps plants green and delays the drying the cobs need. 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 popcorn 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 popcorn

Use the vegetable-feed label rate for popcorn. 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 popcorn first if the soil is dry, then apply the diluted feed. The companion question is when to water at all, covered in the popcorn watering schedule.

Signs you are over-feeding popcorn

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

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.

Signs you are under-feeding popcorn

Pale, yellow-green leaves, oldest first, and slow growth.
Small, tough, bitter leaves and premature bolting.
Weak, stunted heads in cabbage, broccoli and cauliflower.

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

Flushing and leaching the salts

For container-grown popcorn, 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 popcorn

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 popcorn — frequently asked questions

What fertiliser does popcorn 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. Popcorn 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 popcorn?

Moderate feeder. A balanced base dressing plus a nitrogen side-dressing when knee-high is ample; avoid heavy late nitrogen, which keeps plants green and delays the drying the cobs need. Moderate feeder. A balanced base dressing plus a nitrogen side-dressing when knee-high is ample; avoid heavy late nitrogen, which keeps plants green and delays the drying the cobs need. 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 popcorn?