The Dirt on Dirt
Garden Clippings for November 11, 2017
What can we add to soil to rejuvenate it? Let’s look at the most common soil amendments to get the scoop on healthy soil.
Peat Moss: Hands down, peat moss has always been every green thumbers’ favorite soil amendment. Peat moss helps sandy soil hold moisture and loosens clay soil to improve drainage. Peat moss improves soil texture but does little to improve soil fertility. Use liberal amounts and mix thoroughly with your existing soil.
Bone Meal: Use bone meal to build soil fertility. Contains lots of phosphorous for bigger bolder blooms and stronger roots. Bone meal improves all soils, especially benefitting roses, bulbs and all blooming plants. Rather than instant action, bone meal is slow and steady.
Blood Meal: High in nitrogen and quick acting, blood meal is almost the opposite of bone meal, which is why they are often mixed together in the same package. Use blood meal to give anemic plants an organic shot in the arm. Blood meal has the added benefit of repelling mice and other unwanted rodents.
Compost: Let’s define compost as anything organic that has sufficiently broken down to look like rich dark soil. Might include a blend of everything from egg shells to leaves, to grass clippings, to banana peels. Compost trumps most other soil amendments because it improves soil texture and is chock full of nutrients. Mix generous amounts of compost with your existing soil.
Manure: Like compost, manure improves the structure of soil while increasing its organic nutrient value. Mix manure up to 50/50 with your existing soil. And no, there is little difference between sheep, cow, horse and your neighbour’s manure. If you are a city slicker with a pickup truck you might be able to bum manure from a country farmer friend. If not, bagged manure is odor free and higher concentrated.
Green Manure: Follow the advice of an old farmer and grow a green manure cover crop for a year. In the fall plough the crop into the soil and your garden will be grateful. Use alfalfa, sorghum, legumes, clover or any annual crop that will produce lots of vegetation. Green manure serves as a source of food and energy, stimulating valuable microbial activity in soil. Other benefits are a reduction of weeds in your garden patch and improvement in soil aeration.
Gypsum: for the heaviest clay soil, spread gypsum on the surface. Be generous and put down about 20 kg gypsum for every 100 sq metres of area. Repeat for 3 consecutive years. Gypsum contains calcium and sulfur, but will not boost general fertility.
Lime: My high school chemistry teacher taught that if soil is too acidic, plants are unable to use nutrients that probably already exist in the soil. The solution is to add lime in order to raise the pH and sweeten or neutralize the soil. Apply 10 kg per sq metre of area. The application of lime may also serve to reduce moss and mushroom formation. While lime is not a moss killer, it will neutralize highly acidic soil where moss often thrives.
Kelp Meal: This all-in-one soil improver adds traditional fertilizers (nitrogen, phosphorous and potash) and also boosts plenty precious micronutrients such as boron, copper, iron, zinc, molybdenum and manganese. Like all organic soil amendments, kelp meal will strengthen plants, enabling them to withstand stresses of pests, drought and disease.
Mulch: Good gardeners know that mulch is the ticket to healthy soil and strong plant growth. Mulch keeps weeds down, retains soil moisture, reduces temperature fluctuations and insulates soil to minimize winter injury. Like the forest floor, organic mulches break down over time contributing to soil health. Top up once a year to refresh appearance and maintain a depth of 2 to 3 inches.