How to Balance pH for Whitetop (Cardaria draba) Plants

Balancing the pH for whitetop (Cardaria draba) plants, also known as hoary cress, is crucial for their healthy growth. Whitetop thrives in alkaline soils, so maintaining a high pH level is essential. This comprehensive guide will provide DIY users with step-by-step instructions, home remedies, and advanced techniques to balance the pH for whitetop plants.

Soil Testing: Determining the Current pH Level

Before adjusting the pH, it’s essential to test the soil to determine its current pH level. You can purchase a soil pH testing kit or send a soil sample to a local agricultural extension service. The ideal pH for whitetop is between 7.5 and 8.5.

Lime Application: Raising the pH

whitetopImage source: Pixabay

If the soil pH is below 7.5, you’ll need to raise it by adding lime. The amount of lime to add depends on the soil’s buffering capacity, which is a measure of how readily the soil can neutralize acidity. A soil test can determine the buffering capacity. As a general rule, apply 5 to 10 pounds of ground agricultural limestone per 100 square feet to raise the pH by one unit.

Incorporation: Mixing the Lime into the Soil

After applying the lime, incorporate it into the top 6 to 8 inches of soil. This can be done using a rototiller or a garden fork. This step is crucial because lime takes time to react with the soil and neutralize acidity.

Monitoring: Ensuring the Desired pH Level

whitetop 2Image source: Pixabay

After incorporating the lime, wait a few weeks and then retest the soil to ensure the pH has been raised to the desired level. If not, repeat the process.

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Maintenance: Keeping the pH Balanced

To maintain the ideal pH for whitetop, avoid practices that lower soil pH, such as using acidic fertilizers or allowing soil to become compacted. Regularly monitor the soil pH and reapply lime as needed.

Home Remedies for Balancing pH

In addition to using lime, there are several home remedies you can try to balance the pH for whitetop plants:

Baking Soda

Baking soda is a natural alkaline substance that can help raise the soil pH. Mix 1 tablespoon of baking soda per 1 gallon of water and apply the solution to the soil around the whitetop plants.

Wood Ash

Wood ash is another effective way to increase soil pH. Sprinkle a thin layer of wood ash (about 1/4 inch) over the soil around the whitetop plants and mix it in.


Crushed eggshells can also be used to raise the soil pH. Collect and dry the eggshells, then grind them into a fine powder and mix them into the soil around the whitetop plants.

Advanced Techniques for Balancing pH

For more precise pH adjustments, you can consider using the following advanced techniques:

Soil Amendments

In addition to lime, you can use other soil amendments like dolomitic limestone or calcium carbonate to raise the pH. The specific amount to use will depend on the soil’s buffering capacity.

Soil Acidifiers

If the soil pH is too high, you can use soil acidifiers like sulfur or aluminum sulfate to lower the pH. Again, the amount to use will depend on the soil’s buffering capacity.

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Irrigation Water pH Adjustment

If your irrigation water has a high pH, you can use acidic solutions like vinegar or citric acid to lower the pH of the water before applying it to the soil.

Timing and Environmental Factors

The time required for the pH balancing process can vary depending on the soil’s buffering capacity and the specific techniques used. Generally, it can take several weeks to a few months to see the full effects of the pH adjustments.

The ideal temperature range for whitetop growth is between 60°F and 80°F. Adequate moisture is also important, with the plants requiring regular watering to maintain soil moisture.


Balancing the pH for whitetop (Cardaria draba) plants is crucial for their healthy growth and development. By following the step-by-step guide, using home remedies, and applying advanced techniques, you can create the ideal soil conditions for your whitetop plants to thrive. Remember to regularly monitor the soil pH and make adjustments as needed to maintain the optimal range of 7.5 to 8.5.


  1. Rights-of-Way Vegetation Management –
  2. Cardaria draba – USDA Forest Service
  3. Nutrient Criteria Technical Guidance Manual: Wetlands – EPA