Organic Plant Fertilizer Recipe for Acid-Loving Plants

Acid-Loving Plants

• Most vegetables and flowers prefer a neutral pH level between 6.5 and 7, but some berry bushes and flowering shrubs thrive in an acidic environment. Rhododendrons and azaleas, both members of the genus Rhododendron, with numerous species, varieties and cultivars, prefer a soil pH of 4.5 to 5.5 and most can be grown in U.S. Department of Agriculture Plant Hardiness zones 6 through 9. Camellias (Camellia japonica) are another acid-loving shrub and they grow in USDA zones 7 to 9. One of the best-know acid-loving plants is the blueberry (Vaccinium corymbosum). This garden favorite grows in USDA zones 3 to 7.

Coffee Grounds

• Coffee is very acidic and the leftover grounds are a great source of free organic fertilizer for your acid-loving plants. You can mix them with other scraps and add to your compost pile, or save your grounds separately in a covered container. When the container is full, dump the wet grounds onto several layers of newspaper -- it is best to do this outside -- and leave them in the sun to dry. When the grounds are dry, they can be worked into the soil around your acid-loving plants to help lower the pH. If you're not a coffee drinker, ask your local coffee shop to save some for you.

Wood Chips

• Wood chips and aged sawdust are another good source of organic fertilizer for acid-loving plants, especially blueberries. Spread 4 to 6 inches of wood chips or sawdust in the fall on an area where you plan to put acid-loving plants in the spring. Let the wood chips rot for a few months, and when you are ready to plant, the soil should be ready for your blueberry bushes, camellias or rhododendrons.

Commercial Organic Fertilizers

• You can buy already prepared mixtures to fertilize your acid-loving plants. Make sure the product is labeled organic. The term "natural" really has no meaning in terms of fertilizer ingredients. Other organic fertilizers that you can purchase to amend the soil around acid-loving plants are blood meal, feather meal and fish emulsion. Blood meal and feather meal are powdered and can be sprinkled around the base of the plant. Fish emulsion is sold in liquid form and is usually applied using a garden sprayer.