NPK

NPK stands for nitrogen (N), phosphorus (P), and potassium (K). It's not magic: it's the backbone of almost any fertilizer. Other micronutrients matter, but these three drive visible growth.

What each letter does

N: green leaf and growth. Low N: old yellow. High N: pretty plant with few fruits. P: roots and floral initiation. K: fruit, water stress, and flavor. A tomato in fruiting needs more K than a lawn.

In coco and soil

Universal soil provides an initial boost. Coco does not. Fertilize gently from transplanting. Out-of-range pH can mimic an NPK deficiency that doesn't exist.

What we recommend at Control Garden

Before buying more fertilizer, check drainage, pH, and pests. At Control Garden, the draining substrate prevents half of the false “deficiencies.”