Tag Archive | Fertilizer

The Value of Manure

Nutrient values of manures vary greatly, depending on the diet and age of the animals, and the nature and quantity of bedding in the mix. There’s also freshness to consider: the older the manure, the fewer nutrients it will contain. On the other hand, the older it is, the sooner it will be safe to use and the less fragrant it will be.

These variables make precise nutrient listings impossible, but there are significant differences between manure types that are useful to know.

Poultry: Hen dressing, as it’s known in the country, is higher in nitrogen than other common manures. It also contains a significant amount of phosphorus, and some potash. Chicken manure from a farm where birds run around in straw will be considerably less potent (and probably less full of antibiotics) than manure from an egg factory where birds live crowded together in wire cages. Chicken manure is famous for burning plants if it is used when too fresh.

Sheep: Comparatively high in nitrogen, an excellent source of potash, with moderate phosphorus. Manure from sheep fed hay and grain will be more potent — and more likely to be available — than manure from animals that live on pasture.

Horse: About half as rich in nitrogen as chicken, with a good amount of potash but only a modest dose of phosphorus. Amounts of bedding vary greatly, which means potency does, too. Horse manure can be a powerful carrier of weed seeds.

Cow: Cow manure has the lowest nutrient numbers, in part because there is so much bedding mixed with it. But that low nutrient concentration makes it safe to use in unlimited quantities. Try to find manure that’s mixed with straw or shredded newspaper, rather than the more common sawdust. If you get the sawdust kind, expect it to take a year before it starts to deliver results.

Specialty: Rabbit manure is very high in nutrients and less likely to cause nitrogen burn than chicken manure. Most rabbit owners know this and do not give it away. Bat guano is like supercharged chicken, but it’s hard to gather, getting rare, and priced accordingly. Zoos need the money more than you need hippopotamus droppings, but if you have enough land to pile weird manure until it’s composted, the charity you spread will improve your soil.

Fall Lawn Fertilization

by Lisa Johnson, horticulture educator for Dane County UW-Extension

Man_applying_fertilizerFall is the most important time to fertilize your lawn. If you only do it once a year, do it now! Research, based on the growth cycle of turfgrass, shows that Labor Day is the best time to fertilize. Memorial Day is the second-best. Fertilizer is most effective when the highest amounts of root and shoot biomass are present to absorb and use it. Nitrogen, phosphorus and potassium are the macronutrients that lawns need most. Test your soil before applying fertilizer blends so you know whether fertilizer is needed and what type to buy.

Apply no more than 1 pound of nitrogen per 1,000 square feet per feeding, and a maximum of 4 pounds per year. Nitrogen is usually the limiting factor in turf growth, because it doesn’t accumulate in soils as phosphorus and potassium do. Lawn maintenance fertilizers with 25 to 50 percent of the nitrogen content in a slow-release, or water-insoluble form are best. They release nitrogen slowly rather than all at once, minimizing nitrogen loss due to leaching. Leaving grass clippings on the lawn and applying 1/4 of compost reduces nitrogen fertilizer needs, too.

There is a statewide ban on phosphorus in turf fertilizers, with an exception for some organic products in some counties of Wisconsin. Phosphorus, which helps build strong roots, may be recommended in soil tests if you are starting a new lawn from seed or maintaining a lawn in low-phosphorus soils. If testing recommends application, bring your soil test results to the store in order to purchase turf fertilizers containing phosphorus. In south-central and southeastern Wisconsin, we often have high to excessive amounts of phosphorus in our soils (especially in urban soils), so more is not recommended. However, this isn’t the case statewide.

Potassium helps turf increase its disease and drought resistance and prepare for winter dormancy. Potassium is present in higher amounts in winterizer turf fertilizers, but this doesn’t mean you can only apply it in fall. In many areas of Wisconsin, we have high potassium levels in soils, so it may not be needed.

 

 

Wet vs Dry Fertilizer

Dry fertilizers are easier (and quicker) to apply, especially when large areas are involved, and though they are slower to take effect, they last longer. In most gardens, wet fertilizers are used for foliar feeding, sprayed directly on plant leaves for immediate uptake. They produce rapid results, but their action is short-lived.

Dry fertilizers are usually mixed with soil before planting. Later in the season they are used as side dressing, spread in a narrow band about a foot away from growing plants and then scratched in.

Ideally, dry fertilizers break down slowly, providing a steady stream of nutrients with minimal danger of root burn, weak hypergrowth, and other problems caused by too much, too soon. In practice, however, this doesn’t always work out. Dry chemical formulations are highly soluble, and while they are more durable than liquids, they disperse rapidly in warm, wet weather. They can work well, but it is important to use minimum amounts, mix them well with the soil, and keep them away from plant roots.

Most organic amendments, on the other hand, are minimally processed. They must be broken down by weather and soil microbes before the nutrients they contain are available to plants. While there are exceptions, as a general rule these natural products pose none of the dangers of rapid breakdown, and unlike chemical fertilizers, they offer long-term soil-building benefits. But there’s no denying they’re slow to download; you have to plan well ahead.

Summer Lawn Fertility

by Sharon Morrisey, consumer horticulture agent for Milwaukee County

Research by University of Wisconsin turf specialists suggests new recommendations regarding summer fertility for lawns. An application of lawn fertilizer around the Fourth of July might be warranted.

This recommendation is made for:

  • Lawns less than 15 years old
  • Older lawns that have not been regularly fertilized for the last 15 years
  • Lawns where the clippings are collected, rather than left on the ground

This summer application is in addition to fertilizing around Memorial Day and Labor Day. Each application should provide 3/4-1 pound of actual nitrogen per 1,000 square feet of lawn, but follow the manufacturer’s recommendations on the bag.

Fertilizer applications should be followed by watering or applied just before it rains.

Do You Feed Your Trees?

tree-970850_960_720Here’s a question that tends to divide folks right down the middle. When it comes to the wisdom of feeding trees, expert opinion is sharply — in some cases acrimoniously — divided, but the weight of modern practice is increasingly in favor of the dictum that less is more.

A small amount of fertilizer is fine. It will help compensate for the absence of natural fertility that tends to distinguish lawns (where all the leaf litter gets raked up and there is no understory to speak of) from woodlands (where the trees are nourished by lots of decayed plant material).

Fence_and_tree_lined_lawn_Little_Laver_Road,_Essex_EnglandBut before you go out and buy tree food, remember that the small amount needed is likely to be already present as a by-product of fertilizing the lawn. Once you get into adding more than that, it’s likely you will do more harm than good — if you do anything at all. The harm comes because fertilizer pushes the tree into making lots of tender, soft growth. It’s lush, it’s green, it’s very impressive, and it’s also highly vulnerable t insect attacks, climate stress, and the myriad fungus diseases that would be thwarted by tougher tissue.

The doesn’t-do-anything-at-all situation results from putting the food where the tree can’t get at it. Most of a tree’s feeder roots are in the top 10 to 18 inches of soil, and most of them start near the out edge of the canopy (the drip line) and spread outward from there. That means using an injector to put the eats down deep is not going to do much except pollute the groundwater. And spreading the tree’s meal close to its trunk will be just as fruitless.

The bottom line: keep feeding to a minimum unless the tree is in a container where it cannot possibly find nourishment on its own. And if you do use fertilizer on a landscape tree, spread it in a wide band that works out from the drip line.