Improving Melon Fruit Firmness

Most melon consumers are looking for a fruit with firm flesh. Melon firmness is therefore key.

Crop Nutrition and Melon Fruit Firmness


A lot of calcium is taken up during early plant growth. This encourages vigorous leaf production. A relatively small proportion of this – 15% - is found in the fruit, these levels of the nutrient are critical in maintaining good fruit firmness with minimal cracking.

Lack of melon firmness can be a result of poor calcium nutrition. High levels of calcium thicken cell walls and firm the fruit. However, calcium needs to be balanced with adequate supplies of boron to prevent cracking. Trials confirm that calcium nitrate is particularly effective at ensuring good fruit quality.


Magnesium uptake however, can be depressed by an excess of other cations (potassium, ammonium and calcium) so it is important to maintain a correct balance to avoid compromising uptake. An imbalance of cations will lower peel firmness. Magnesium – in balance with potassium and calcium – ensures good pulp firmness.