What do the three numbers on the bags and boxes of fertilizer mean?

They represent the percentages of plant nutrients by weight. Just remember "up, down and all around." The first number represents the nitrogen, the second represents the phosphorus and the last one represents the potassium. These numbers are always expressed in the same order.

In fertilizer what is nitrogen needed for?

It's the up. It promotes plant growth and greening, thus providing more foliage, color and density.

In fertilizer what does phosphorous do?

This is the "down" number. It stimulates cell building and root growth and is particularly beneficial in helping seedlings, flowers and vegetables to develop.

In fertilizer what does potassium do?

It assists plants in forming starches and proteins, thus promoting plant hardiness, disease resistance and a tolerance to drought and cold. It's the "all-around" number.

What is a good all-around, multi-purpose fertilizer?

A 12-12-12 helps promote growth and is good for all vegetables, flowers, fruit and nut trees, shade trees, evergreens and shrubs. A 1-1-1 ratio (10-10-10,15-15-15, 20-20-20, etc.) is widely used at the time of lawn establishment, but established lawns generally respond better to fertilizer ratios high in nitrogen. Two of the more common complete fertilizers used by homeowners for flowers and vegetables are 10-10-10 and 5-10-10. A high phosphorus fertilizer such as 6-18-6 is often recommended for vegetables when transplants are set out.

What are special-purpose fertilizers?

Some fertilizers are designed for certain uses or types of plants such as citrus food, rose food or azalea food. For example, azalea fertilizer has been specifically formulated to acidify the planting medium. Packaging of other fertilizers for specific types of plants is often based more on marketing then reliable research. Pick the most inexpensive product that supplies the correct amount of needed nutrients.

What are the advantages of synthetic fertilizers?

They're faster acting than organic making them a good choice for aiding plants in severe distress from nutrient deficiencies. These fertilizers, which come as dry, granular pellets or water-soluble products, also provide even, consistent feeding.

What are the advantages of granular pellets?

They are usually less expensive than their organic counterparts. They can be applied by simply spreading them around plants or using a spreader to apply them to a lawn.

What are time-released granular pellets?

These controlled-release fertilizers provide consistent feeding for three to nine months, depending on the product. The fertilizer granules are coated with a permeable substance. With each watering, a bit of fertilizer diffuses through the coating and into the soil. Advantages include the need for fewer applications and less of a chance of burning the plant. However, they do not provide as quick a boost and they cost more.

What are the advantages of water-soluble fertilizers?

These dry or liquid concentrates must be diluted in water before application. They are applied with a hose-end sprayer or a watering can. They are relatively expensive, but they are easy to apply and provide even feeding. They are easy to use, especially on container plants. There is no risk of burning a plant as long as you follow label directions for dilution, and the nutrients, in solution, are available to plant roots immediately. They are less practical than the solids for large-scale use because of their greater cost and because they must be reapplied more often (their nutrients in solution leach through the root zone more rapidly).

What are the advantages and disadvantages of organic fertilizers?

The word "organic" simply means that nutrients contained in the product are derived from a once-living organism. Most are high in just one of the three major nutrients and low in the other two. Their major advantage is adding bulk to the soil. Except for manure, the organics generally release their nutrients over a fairly long period. However, the potential drawback is that they may not release enough of their principal nutrient at a time to give a plant what it needs for best growth. Because they depend on soil organisms to break them down, most organic fertilizers are effective only when the soil is moist and warm.

When should I apply fertilizers to plants and trees?

Don't apply liquid fertilizer at the same time you plant. Some root hairs will break, and the fertilizer will burn them. Wait two to three weeks after planting before you fertilize. In general, apply fertilizers to plants at the beginning of the growing season. For deciduous trees, fertilize when leaves appear; and for evergreens, when it turns cold. Shrubs do not require much fertilizing.

Can I spray my fruit trees from the ground?

Yes, a hose-end tree sprayer will do the job, but will often end up applying the chemical to other surrounding plants and the lawn. Consider using a ladder and a regular hose-end sprayer or pump sprayer.