Satisfy Acid-Loving Plants with Sulfur

Even if your soil isn't naturally acidic, you can grow acid-loving plants like azaleas, rhododendrons, or blueberries, says Dan Hartmann, general manager of Hartmann's Plantation in Grand Junction, Michigan. The secret is to add the right amount of sulfur to the soil to lower the pH. Dan explains how to figure out "the right amount."

Ingredients and Supplies
Soil pH test results
Granular or powdered sulfur
Peat moss or acidic compost

Directions
1. Before you can determine how much sulfur to add, you need to get your soil tested to find out the pH. Check with your garden center or local extension office for information on testing services,- home test kits are also available.
2. Use the chart on the facing page to determine how much sulfur to add to lower the pH to about 5.5, which is low enough for blueberries and many other acid-lovers.
3. "If possible, apply the sulfur to the planting area in the fall," Dan advises, "or at the very least 1 month before you plant in the spring."
4. If you absolutely have to plant immediately, amend the soil in the planting hole with up to 50 percent peat moss. Then apply the sulfur to the top of the soil just beyond the planting hole. The naturally acidic peat moss will get the plants started and by the time their roots reach into the soil outside the peaty area, the sulfur will have had time to lower the pH.
5. Dan says you'll also need to add more sulfur in the future. "Probably every year if you started with a pH 7 soil,- every other year for pH 6.5,- and every 3 to 4 years if your soil was pH 6." He cautions that you should apply sulfur only in the winter when the plants are dormant.