Gardening Guide

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Soil Recipe for Acid Loving Plants



Plants that thrive in acidic soils but can be grown successfully in North Texas include: azaleas, gardenias, dogwoods, camellias, Japanese maples and blueberries.  In our North Texas clay soil, planting in raised beds that are 8-12 inches above the original soil level is the simplest way to give these plants the conditions they need. The soil must also be amended below the original soil level to a depth of 4-6 inches for optimum plant performance.

To prepare the bed, dig out the existing clay soil to a depth of at least 6 inches, removing any undesirable vegetation or weeds. Next, add the following amendments in order per 50 square feet of bed area to build up the bed level at least 8 inches:

• Expanded Shale – 40 lb. bag – 2 bags
• Covington’s Soil Builder – 1.5 cubic ft. bag – 12 bags
• Peat Moss- 3.8 cubic ft.- 1 large bale
• 4 lbs. dry molasses
• Soil Sulfur – ½ lb.

Spread the first three ingredients evenly throughout the entire bed. Lightly work the sulfur and molasses into the soil, broadcasting them throughout the bed, then add:

• Azalea Planting Mix – 2 cubic ft. bag – 14 bags
(Specially formulated by the Dallas chapter of the Azalea Society of America)


• Covington’s Soil Builder – 1.5 cubic ft. bag – 16 bags

Fertilize at time of planting with Happy Frog 6-4-4 for Acid Loving plants or fertilizer which is specially formulated for acid loving plants.
For Japanese maples, fertilize with Happy Frog 4-8-5 Japanese Maple Food.

A 20-30 Gallon container will work best.  Good choices include whiskey barrels and high grade plastic containers. Be sure that your container has adequate drainage holes. A soil pH of 4.0-5.5 is necessary for blueberries to thrive.

Fill the container with:

• 3/4 Peat Moss
• 1/4 Expanded Shale


• ½ Azalea Planting Mix
• ½ Covington’s Soil Builder
Fertilize at time of planting with Happy Frog 6-4-4 for Acid Loving plants or fertilizer which is specially formulated for acid loving plants.  Add 2 inches of Azalea mix or shredded cedar mulch to the top of soil.
Covington’s Soil Builder is three great soil amendments in one convenient application. It contains Back to Earth Composted Cotton Burrs, Expanded Shale and one pound of Texas Greensand.
Did you know that the flower color of big leaf Hydrangeas is pink or blue depending on how acidic the soil is?
At a pH between:
• 4.5 and 5.0 – flowers are blue as a result of aluminum in the soil
• 7.0 and 7.5 – flowers are pink as a result of the alkalinity of the soil
If your Hydrangea is producing pink flowers and you would prefer blue, spread a pound of aluminum sulfate per square yard under the bush in the early spring and again in the fall. The blue flowers can be changed to pink by adding a pound of ground limestone.

2                                                          Revised 1/15/15