Raising Vegetable Yield: Which Fertiliser, and When?

The key to higher yield in vegetable growing

The most effective yield boosters in vegetables are fertiliser combinations applied with the right element, at the right rate and at the right time. Vegetable growing is a fast process · in species such as tomato, pepper and aubergine the plant reaches full production capacity in 60–90 days. That speed means nutritional mistakes turn into yield loss very quickly.

Strategies by vegetable type

Tomato

Tomato has high yield potential and is also among the species with the highest nutrient demand. For 10–15 tonnes per decare and above, this nutritional balance must be maintained:

• Balanced nitrogen + zinc in the vegetative period
• Zinc + boron reinforcement during flowering
• Concentrated potassium during fruit development

Pepper

Pepper is a multi-harvest crop. After each harvest wave the nutrition programme should be renewed, with zinc and potassium supplementation in particular. The interval between irrigations is critical for pepper: water stress causes flower drop, while excess water leads to root disease.

Cucumber

Fruit set is very fast in cucumber and the plant spends energy continuously. Calcium and magnesium deficiency is common and shows itself as interveinal chlorosis on the leaves. Regular magnesium + zinc foliar fertiliser protects productivity.

Fertiliser programme by growth stage

Seedling and early vegetative stage

Root development and the formation of the first leaves are the priority. A balanced starter fertiliser containing zinc and iron roots the seedling quickly and protects it against early chlorosis. Casablanca gives the season a strong start with a first foliar application 5–7 days after planting.

Flowering

The greatest source of loss in vegetable growing is flower drop during flowering. A zinc + boron combination should be applied weekly in this period.

Fruit development

This is when the plant's nutrient requirement peaks. Potassium, calcium and magnesium come to the fore. Nitrogen should be restricted · excess nitrogen does not grow the fruit, it only produces leaves.

Harvest and after

In multi-harvest species the plant re-enters flowering after each pick. Repeating zinc + boron through this cycle maintains continuity of yield.

Common mistakes

• Applying nitrogen only: nitrogen grows leaves, but yield needs the other elements too
• Intervening late: by the time a deficiency symptom is visible the damage has begun; a preventive programme is essential
• Applying in full sun: foliar fertiliser applied at midday scorches
• Not checking pH: outside soil pH 6–7 the fertiliser does not dissolve and cannot be taken up

Frequently asked questions

Which is the best fertiliser for increasing vegetable yield?

There is no single "best fertiliser"; a stage-based programme is needed. Zinc + iron in the vegetative period, zinc + boron at flowering, potassium + calcium during fruiting.

How often should foliar fertiliser be applied?

Every 10 days in critical periods (flowering, fruit development) and every 14–21 days at other times.

Can liquid fertiliser be used in organic vegetable growing?

Casablanca is produced from naturally sourced raw materials and fits a residue-free approach. In certified organic production, documentation should be verified before use.

Are trace elements as important as macro elements?

Although trace elements are needed in smaller amounts, their presence matters far more than their quantity suggests. A zinc deficiency will cripple yield no matter how much nitrogen and phosphorus is applied.