Phosphorous & Potassium

Phosphorous

As the season moves towards the flowering and fruit set stage, switch to a formula higher in Phosphorous. Flower growers like Phosphorous to help promote big, bright blooms. 5-10-5 or 5-15-5 are common ratios. If you do not want to worry too much about what fertiliser to use, this is a good overall ratio for the entire year.

Phosphorous will promote both root growth and fruit set and development. Phosphorous is more forgiving as it does not burn your plants. It is less water soluble, so an over-application will not do major harm to your plant.

Potassium

This chemical will promote fruit growth. After fruit set, you should either switch to a high potassium fertiliser, or supplement your feedings with extra potassium. Like Phosphorous, it will not burn your plants. Over application however, along with all the other ingredients (sun, water, rich composted soil) can have negative affects on your plant. Take it easy early in the fruit development stage, especially if you are a new grower.