The pH Requirements for Dracaena

Soil pH

• The pH scale measures the alkalinity or acidity of a substance -- in this case, soil. The pH scale ranges from 0 to 14, where anything above pH 7 is alkaline, anything below pH 7 indicates acidity, and pH 7 is neutral. Various plants and trees require a particular soil pH range in order to thrive and can become sickly or die if grown in soil that's outside their preferred range.

Ideal Soil pH for Dracaena

• Dracaena plants prefer a soil pH level between 6.0 and 6.5. Levels below 6.0 can lead to fluoride toxicity, while pH levels above 7.0 can cause iron deficiencies. To maintain proper soil pH, avoid using perlite, superphosphate and other fluoride-containing soil amendments. It's recommended that you not irrigate your dracaena with water containing more than 1 part per million of fluoride. Many dracaena aficionados irrigate with distilled water rather than tap water, which often contains higher-than-desirable levels of fluoride.

Testing Your Soil

• Soil testing kits allow you to test your potting soil's pH level and determine whether it is suitable for growing dracaena. You can purchase an inexpensive soil testing kit at a garden or home improvement center, where you can also buy pH meters -- another method of soil testing. Testing devices are also available online.

Amending Your Soil

• You can amend your soil with additives if your soil falls outside the desired range for dracaena. If your potting soil is below pH 6, you can add dolomite lime (1 ounce per 1 gallon of soil) to raise the soil pH. If your potting soil is above pH 6 , you can add granular sulfur, sprinkled on the soil's surface or mixed with water and poured into the soil, to safely lower the pH. One-half teaspoon of sulfur per 6 inches of pot diameter will lower pH by half a point. Changing potting soil pH can take time, so patience is required. Check your soil two weeks after each amendment, and reapply additives if necessary.