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Fertilizers 101 Nurseryman Richard Kline offers an FAQ on fertilizers and soil amendment. From "The Dirt On..." episode DTDO-104

Nurseryman Richard Kline offers advice on the different types of fertilizers and their proper use.

Master Nursery Professional Richard Kline stopped by to give a lesson in "Fertilizerz 101."

Should you buy an all-purpose fertilizer for all your plants or specific types for each plant?

All-purpose fertilizers will work okay for all your plants, but they won't work great on any of them. For the best results you really should get specially formulated types such as a "tree and shrub" or even a specific plant like an "azalea" fertilizer.

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What do the numbers on the packages refer to?

The numbers refer to the percentages of different ingredients. The first number refers to the percentage of nitrogen in the fertilizer, which encourages green growth. The second number refers to the percentage of phosphorus, which encourages strong root growth. The third number refers to the percentage of potassium, which encourages stronger stems.

What difference would you notice if you use organic instead of synthetic?

A synthetic fertilizer will give your plants a quick fix because it is readily available for your plant to absorb. Organic fertilizers need time to break down in your soil but they will improve your soil conditions in the long run.

	Figure A
	Figure B
	Figure C

Which application methods do you recommend for different types of plants?

For trees, root feeders (figure A) work well because they send both water and fertilizer directly to the root zone so your neighboring plants won't steal it all. It's a long probe with a cartridge on the end that holds fertilizer pellets and screws into your garden hose. Stick this into the soil next to your tree and it will deep water and fertilize at the same time.

Liquid or granular fertilizers (figure B) work well for shrubs, and the specific mixes for individual plants will give you the best results. You always want to dilute liquid fertilizers before applying, following the label directions, to give your plants the right amount. If you are using a granular fertilizer, spread it either by hand or with a spreader around your plants when it is dry. Rake it into the soil and water it in.

Water-soluble fertilizers work well for flowers, especially when you use one specifically formulated to boost blooms. These fertilizers will have a high middle number. You can find them with numbers up to 52, which means 52 percent phosphorus. Apply these fertilizers with an applicator that attaches right to the end of your hose (figure C) . The water will run through, mixing with the fertilizer, and you simply water as usual right over the foliage too. In this way, the plants are watered and fertilized at the same time.

Go to next article in DIY's "Gardening Basics" series.