Edwina von Gal’s RADICLE Thinking

Last week, we talked about the benefits of natural fertilizers like compost and compost tea. So what's the difference between the two? Why brew tea when you could just apply compost?

COMPOST:

+ High in microbial content to feed your soil
+ Contains some soluble nutrients to feed your plants
+ Rich in organic matter that helps improve soil structure
– Heavy and messy to apply
– Will end up all over your clothes (and your kids and pets) if you play on a lawn treated with compost. Best to apply in spring or fall.

COMPOST TEA:

+ High in microbial content to feed your soil
+ Contains some soluble nutrients to feed your plants
+ Only requires a small amount of compost to feed a large area of land
+ Easy to apply throughout the year using a sprayer or watering can
+ Good for lawns or gardens that need to recharge their microbial battery
– Does not contain organic matter for your soil
– Requires special equipment to brew (but our how-to instructions make it easy)

Need to give your plants a little kick this summer? Here's what you need to know before you pick a fertilizer:

The main difference between conventional synthetic fertilizers and organic slow-release fertilizers is solubility, or how quickly they dissolve in water.

Synthetic fertilizers dissolve rapidly, releasing nitrogen quickly into the soil. They promote quick "green up" and shallow root systems. They quickly leach into ground or surface waters when it rains, preventing most of the nitrogen from actually being absorbed by your plants. This causes pollution that can lead to algal blooms. Over time, synthetic fertilizers can build up in your soil and kill the microbes that keep your soil and plants healthy.

Slow-release organic fertilizers, along with compost and compost tea, work by providing beneficial microbes and food for microbes already living in your soil. These microbes, in turn, produce nutrients for your plants. These fertilizers are less soluble than synthetics, leading to less leaching of nutrients, and lessening the need for frequent fertilizer applications.

Many landscapers now provide compost tea applications, or you can check out our how-to for brewing your own.

You can buy a compost tea brewing system or make your own at home. Whichever system you use, you will need a heavy-duty pump to aerate the water sufficiently. Proper aeration encourages beneficial microbes to multiply and discourages harmful microbes from growing in your tea. A fish aquarium bubbler will not be strong enough.

1. Start with great compost. Blending two or three composts together will give you a great variety of beneficial microbes. Put your compost in a mesh strainer bag (you can find them at the local hardware store in the paint section).

2. Fill your brewer with water and run the pump for 20 minutes to de-gas any chlorine.

3. Put your compost bag in the water while the brewer is running. Hang the bag from the edge of the bucket to expose as much of the compost as possible to the bubbling water.

4. Check the color of the water to make sure it is getting significantly darker, which indicates that microbes are being extracted from the compost.

5. Add food to feed the microbes. Suggested foods include molasses, kelp, humic acid, and fish emulsion.

6. Brew for 24 hours.

7. Decant your tea and use within six hours. Mix two parts water with one part compost tea and apply using a watering can or sprayer.

8. Clean your brewer immediately.

9. Brew more tea!

Got new trees and shrubs? Drip irrigation can be an effective way to keep them well-hydrated this summer, but keep in mind the following before you put down those hoses:

• Place drip tubes beyond the root ball, as well as on it, to encourage roots to grow into the surrounding soil.

• Water newly planted trees and shrubs seldom (less often than your lawn) and deep (12-18"). Too much watering encourages excess growth, a magnet for fungus diseases and sucking insects.

• Remove tubes after two years. Your plants will be well-established and just won't need the irrigation anymore.

Photo credit: U.S. Department of Agriculture

So, you are leaving your clippings for 80% of your lawn’s nutrient needs. What is free and easy to add to that? If you’re lucky, the PRFCT ingredient is already growing right beneath your toes.

Clover is a nitrogen fixer—it pulls nitrogen from the air and releases it back into the soil when mowed. Those nitrogen-fixing roots run deep, keeping clover green even in hot, dry months. Your grass will love the nitrogen boost every time you mow, and the environment will love you for not adding more fertilizer.

Worried about bees? It's true that bees (and butterflies!) love clover flowers, but they are not aggressive away from their hives. Bees feasting on clover flowers should not sting unless stepped on directly. You can prevent stings by avoiding large clover patches, wearing shoes when on a flowering clover lawn, and mowing as soon as the flowers open. The cut flowers are also nitrogen-packed, so be sure to leave them along with the rest of your clippings.