Do Strawberry Plants Absorb Fertilizer Through the Berries?

Foliar Fertilizers

• Foliar fertilizers are sprayed on the top portion of the plant so that the leaves will absorb them directly instead of waiting for absorption through the roots. They are specially formulated so that they won't burn the foliage. The fruit of any plant, including strawberries, does not readily absorb fertilizers. They may absorb small amounts of certain chemicals through their berries, but not the entirety of the fertilizer solution, and not in a beneficial fashion.

Chemical Burn

• When fertilizers that are not designed to be used on foliage are used on the foliage of strawberry plants, the chemicals in them may burn the strawberries. The outer skin of the berry suffers damage from the contact, and lower layers are in jeopardy of damage through the damaged portions of the outer skin. This damage invites pest problems and makes the fruit inedible.

Edibility

• Even when the strawberries do not absorb the fertilizer directly, fertilizers can contaminate the strawberries if the solution does not get thoroughly washed off. There are fertilizers and foliar sprays recommended for use on food crops, but even these are not usually used while fruit is on the plant to avoid fruit drop or contamination. If in doubt, put off fertilization until after the last harvest.

Considerations

• Many extension centers recommend fertilizing strawberries soon after transplanting (or while the foliar growth is the strongest) and after harvest. None recommend fertilizing while the strawberry plants are in flower or while they are producing fruit, to avoid blossom- and fruit-drop problems as well as berry damage and contamination problems.