When and How to Use Manure in the Flower and Vegetable Garden

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Manure is an excellent organic soil amendment and fertilizer for a flower or vegetable garden, however; to use it safely on edibles, it must first be composted, or aged for at least a year.

According to the Oikos website, "Composting is the controlled aerobic (oxygen-using) biological decomposition of moist organic (biologically derived carbon-containing) solid matter to produce a soil conditioner."

The primary purpose of composting manure is to raise the temperature to a point where all harmful microorganisms are destroyed. Fresh manure contains all the microorganisms of the body it came out of, be it animal or human, and is not safe for use in a vegetable garden.

Another reason for composting is that fresh manure is very hot, and will burn tender plant roots. Composted manure has used up all its heat during decomposition, so it does not burn.

Manure is used to lighten, or add organic matter to, heavy or sandy soils to create a medium more conducive to healthy plant growth. Manure also has some nutritional value, albeit in low amounts. In organic gardening, it is believed that these small amounts are more readily absorbed by plant roots, giving the plants more nutrition than gained by using chemical fertilizers.

When using composted manure as a soil amendment in a flower garden, its best to mix it in equal parts with the garden soil. When using fresh manure, a 1:3 ration should be used, to avoid burning.

Break up any clods in the manure, and spread it out on top of the soil, then vigorously mix it in to a depth of about 9-12 inches.

It's best to mix fresh manure into the soil in the fall, and let it sit in the soil until spring. If that isn't possible, let it sit at least two weeks before planting. Using fresh manure in soil where seeds will be planted can kill the seedlings.

Only composted manure should be used in the vegetable garden, and it should be mixed in a 1:1 ratio with the soil.

It is safe to use manure fresh (not composted) on ornamentals, although care must be taken not to use too much, due to the danger of burning the roots. Fresh manure is best used around ornamental shrubs or trees. If used in the flower garden, fresh manure must be used as a side dressing, placed in small amounts a few inches away from the roots of the plants.

Composted manure may be spread in as great a quantity and as close to the plant as you please, and maybe used in the vegetable garden as well.

Where you get your manure is very important. If you are using manure from animals that have been eating feed treated with chemicals, those chemicals are still in the manure, and will be added to your soil, and perhaps absorbed into your edible crops. The only way to be absolutely sure what chemicals are in your manure is to either buy a reliable, organic composted manure or get your manure from a totally organic farm.

When you use manure in the vegetable garden or in the flower garden, be sure that by recycling this natural product back into the environment you are not doing it harm as well.