Natural Fertilizers: Part I
Wouldn’t it be great if you could feed your lawn and landscape without ever going to the garden center? Nothing against garden centers, mind you. If I have to shop, that’s where I like to go.
My point for this post, though, is that you don’t necessarily HAVE to buy bagged products to apply to your gardens. All sorts of naturally occurring materials can be used as fertilizers. Here are just a few (as culled from my book, The Organic Lawn Care Manual):
For years, animal-based products led the way in fertilizers. People never thought twice about manure from cows, chickens, and other farm critters. Then along came fears about mad cow disease, E. coli, and other pathogens associated with animal waste. Suddenly, gardeners were taking a second look at plant-based soil amendments, some of which have wide practical application for lawns.
Often available in pellets containing approximately 3 percent nitrogen, alfalfa meal is readily available at farm stores as an inexpensive animal feed. It works well as a lawn soil amendment, probably because it’s a grass product.
A by-product of the milling of corn syrup products, corn gluten has been marketed as a pre-emergent weed suppressant since 1991. A thin layer of the material applied on lawns and gardens inhibits the germination of seeds (although I think it’s oversold in this regard). High in proteins, corn gluten also contains significant amounts of nitrogen, up to 10 percent. Just don’t apply it at the same time you’re trying to overseed your lawn; the seeds won’t germinate.
A rich source of nitrogen at 7 percent, cottonseed meal is popular as a fertilizer in some areas of the South where cotton is grown. Most organic certifiers reject cottonseed meal, however, since the majority of cotton in the United States is heavily sprayed with pesticides.
A component of many high-end natural fertilizers because of its high nitrogen content, about 7 percent, soybean meal is on the expensive side.
The anecdotal evidence has always been there. Gardeners in England and Ireland, where seaweed is plentiful, gather every speck they can find. If you’ve ever seen one of their gardens, you’d have to believe the stuff works. I’ll never forget visiting the organic gardens of Olympic gold medal marathon champion Joan Benoit Samuelson, who lives by the shore in Freeport, Maine. She harvests seaweed by the bushel and lays it in the rows between her plants, and her soil is amazing.
Much of the new generation of bagged fertilizer products has embraced seaweed as one of the key ingredients. Myriad studies have shown kelp contains all 16 elements needed for plant growth as well as a particular hormone known as cytokinin, which is responsible for cell division and cell enlargement. Cytokinin is often lacking in lawns that have suffered root declin and kelp can help restore root vigor. Many organic lawn specialists also point to increased seed germination and seedling vigor when seaweed products are applied.
Dried seaweed contains about 1 percent each of nitrogen and phosphorus and 5 percent potassium.
Readily available to people who burn wood to heat their homes, wood ash is often used in place of limestone to raise the pH of soil. On average, wood ash contains about 2 percent phosphorus, 6 percent potassium, and 20 percent calcium. Beware, though: Don’t use wood ash from unknown sources, and avoid wood ash if your soil pH level is already adequate or high.
TOMORROW: Free lunches for the lawn