When should I start feeding tomatoes?

Begin once the first truss of fruit has set, typically in June. Feed weekly outdoors (every 7-14 days), or at alternate waterings under glass where growth is faster. Do not feed before fruit sets — early feeding just pushes leafy growth.

How much Tomorite do I dilute?

Levington Tomorite is diluted at 20 mL (one capful) per 4.5 litres of water — about 4.4 mL per litre. A 1 litre bottle makes roughly 225 litres of ready-to-use feed.

Can I overfeed tomatoes?

Yes. Overfeeding causes lush foliage at the expense of fruit, and the resulting growth surge can trigger blossom end rot. Stick to the label dilution rate rather than making it stronger.

What NPK ratio is best for tomatoes?

A high-potash feed encourages fruiting and flowering. Tomorite is NPK 4-3-8 (plus magnesium and seaweed). General-purpose feeds carry too much nitrogen, which favours foliage over fruit.

Can I use tomato feed on other plants?

Yes. Any fruiting or flowering plant benefits from high-potash feed, including peppers, aubergines, cucumbers, strawberries, and flowering hanging baskets.

GardenCalcs

Tomato Feed Calculator — Feeding Schedules & Quantities

Calculate tomato feed dilution rates and feeding schedules.

Number of Tomato Plants

Plants you'll feed on the same schedule — a 4.5 L can of diluted Tomorite waters roughly 2 plants.

Feed TypeConcentrates dilute in water; ready-to-use is applied neat; soluble/granular feed (e.g. Chempak) is sold by weight.

Feeding Season Length

UK season is about 14 weeks (June-September), starting once the first truss sets.

Water per Plant per Feed

Allow roughly 1 L of diluted feed per plant per feed; large plants in growbags may take more.

Price per bottle (optional)

Price of one bottle or tub — used to estimate total feed cost for the season.

How We Calculate This

Total feeds = feeding weeks × feeds per week. Total water = number of plants × litres per plant × total feeds.

For a liquid concentrate, feed needed = total water × dilution rate. Tomorite's label rate is 20 mL per 4.5 L, i.e. about 4.4 mL per litre — not 10 mL/L. For ready-to-use feed the volume equals the water applied (it is used neat). For soluble/granular feed, grams = total water × the g-per-litre rate.

Packs needed = feed required ÷ pack size. Liquid concentrates are sold in 500 mL or 1 L bottles; soluble/granular feeds (e.g. Chempak) come in tubs sold by weight.

Frequently Asked Questions

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Last updated: February 2026

All calculations are estimates based on standard gardening guidelines. Results may vary with soil conditions, climate, and plant varieties.