Fertilizer, when properly applied, can enormously increase yields in your garden, but sometimes it can be confusing to figure out how much to apply.
This article contains hints and instructions for how to measure and apply the right amount of fertilizer to your crops, plants, and trees.
One of the most basic garden fertilizers is generically called 10-10-10 fertilizer — it contains (by weight) 10 percent nitrogen(N), 10 percent phosphorus(P), and 10 percent potassium(K). This means that 100 pounds of 10-10-10 fertilizer contains 10 pounds of nitrogen, 10 pounds of phosphorus, and 10 pounds of potassium.
Also, a cup of 10-10-10 fertilizer weighs approximately 1/2 pound.
Covering 100 Square Feet of Flowers or Vegetables with 10-10-10
To prepare 100 square feet of garden space for planting, you should apply about .7 lb (seven tenths of a pound) of 10-10-10 fertilizer. Since a cup of 10-10-10 weighs about 1/2 pound, this means you should apply slightly less than 1 1/2 cups of 10-10-10 to the area. Use a shovel or tiller to blend the granules into the soil to a depth of about half a foot.
Covering a 10 Foot by 2 Foot Row of Vegetables with 10-10-10
A 10 foot by 2 foot row of vegetables is 20 square feet, 1/5 the area of a 100 square foot area. This will require 1/5 of 1 1/2 cups of 10-10-10 — 3/10 of a cup of fertilizer (a little more than a quarter cup).
Fertilizing Trees with 10-10-10
The rate for nitrogen is 6 pounds of actual nitrogen per 1,000 square feet. Fertilizer should be applied over an area extending to the edge of the tree crown. The following table lists required amounts of 10-10-10 fertilizer for different size trees.
See http://www.turfcaresupply.com/upload/documents/label/902356%20-%20Back.pdf for more information.