Fertilizer application rates and timing depend on what you’re growing and how fertile your soil is. Test your soil to determine its fertility. In the fall, take several cups of soil from different parts of your garden, and mix them in a bucket.
Take your samples from 2 to 5 inches below the surface, as surface soil may not be representative of that in the root zone. Dry a cup of the composite mix in a sunny window, then submit it to your cooperative extension service for testing. The cost is modest and the information reliable.
Testing The Soil And Applying Fertilizers
The standard soil test indicates the amounts of phosphorus, potassium, and sometimes nitrogen in the soil, as well as the soil texture and pH. Note that soil pH may be slightly lower in the fall than in the spring. The tests for nitrogen are highly variable and unreliable, so don’t put too much faith in that number. Most soil-testing services supply a fertilizer recommendation with the test results.
If you do not wish to take a soil test, broadcast and turn under about 20 pounds of 51010 fertilizer per 1,000 square feet before you plant. This will be adequate to get most plants off to a good start.
Applying Fertilizers
Fertilizer can be applied by broadcasting or side-dressing. With broadcasting, fertilizer is scattered on the soil and tilled under. Do this just before planting; if you do it too far ahead of time, some of the nitrogen and potassium may leach out of the root zone, particularly in sandy soil. If you’re applying fresh manure, work it into the soil in the fall before planting. Broadcast rotted manure a few weeks before spring planting, in a layer 2 to 3 inches deep, and work it into the soil.
Side-dressing is applying fertilizer in a broad band 6 to 10 inches from the base of the plants. This is done during the growing season. Encircle individual larger plants, such as cabbage. A half handful to fertilizer around each transplant should be sufficient. With row crops, like carrots, apply fertilizer along both sides of the row; sprinkle enough fertilizer so that it looks like a very light dusting of snow. Five pounds of 101010 per 100 square feet, or a handful per 10 feet of row, is just about right.
(One cup of fertilizer weighs about a half pound.) Scratch the fertilizer lightly into the soil with a rake. If you’ve applied organic mulch, rain will wash the fertilizer through the mulch into the soil. Side-dressings supply additional nutrients during the second half of the season, when most growth is made. They also resupply some of the nitrogen and potassium that may have leached from the root zone since earlier broadcasting.
Starter solutions are high-analysis, rapidly available, water-soluble and liquid fertilizers that are used to water in plants during transplanting. They are particularly high in phosphorus, which stimulates root growth. Some common analyses are 163216, 202020, and 10528. Organic growers use manure tea. There are several formulas for manure tea. I put a bushel of manure in a 55-gallon barrel and then fill it with water. After stirring the contents, I let it sit for a week. Most of the manure will settle to the bottom. The water component is the tea.
Foliar fertilizers are most useful for supplying micronutrients to the plant. These are needed only in small amounts that can be absorbed directly through the leaves. Don’t try to use these fertilizers to supply the major nutrients; so much would have to be applied that the foliage would burn. Some companies advocate the use of foliar fertilizers on a regular weekly basis to supply all the nutrient needs of the plant.
This may be counterproductive, however, producing huge, viney tomato plants with no fruit, or large, succulent pepper plants that break in the wind. Don’t waste your money on products that seem too good to be true. Instead, follow a sensible fertilizer program.
Article written and provided by Joshua, webmaster of plumber training and becoming a plumber
