How to Balance pH for Geranium Macrorrhizum: A Comprehensive Guide

Geranium macrorrhizum, also known as bigroot geranium, is a beautiful and hardy perennial that adds a vibrant touch to any garden. However, to ensure its optimal growth and health, it is crucial to maintain the proper soil pH balance. In this article, we will guide you through the process of balancing the pH for Geranium macrorrhizum, including the identification of pH issues, specific caring processes, chemical uses, home remedies, and more.

Why is pH Balance Important for Geranium Macrorrhizum?

Geranium macrorrhizum thrives in neutral to slightly acidic soil, with an ideal pH range between 5.8 and 6.5. When the soil pH falls below 6.0, the plant may experience various issues, such as:

  • Burned and speckling leaves due to high levels of iron and manganese uptake
  • Stunted growth and reduced vigor
  • Increased susceptibility to diseases and pests

By maintaining the proper pH balance, you can ensure that your Geranium macrorrhizum receives the optimal nutrients it needs for healthy growth and beautiful blooms.

How to Identify pH Issues in Geranium Macrorrhizum

Geranium macrorrhizumImage source: Pixabay

To determine if your Geranium macrorrhizum is experiencing pH issues, look for the following signs:

  1. Yellowing or browning of leaves, especially along the edges
  2. Stunted growth or lack of vigor
  3. Presence of leaf spots or other unusual markings

If you notice any of these symptoms, it is essential to test the soil pH to confirm if an imbalance is the cause.

Testing Soil pH for Geranium Macrorrhizum

To test the soil pH for your Geranium macrorrhizum, you can use a home testing kit or send a soil sample to a professional laboratory. Home testing kits are readily available at most garden centers and are easy to use. Simply follow the instructions provided with the kit to obtain an accurate reading.

See also  How to Balance pH for Graptoveria: A Step-by-Step Guide

If you prefer a more precise analysis, sending a soil sample to a professional laboratory is the best option. Contact your local cooperative extension office for information on how to collect and submit a soil sample for testing.

Balancing Soil pH for Geranium Macrorrhizum

Geranium macrorrhizum 2Image source: Pixabay

Once you have determined that the soil pH is not within the ideal range for Geranium macrorrhizum, you can take the following steps to balance it:

Using Chemical Amendments

  1. For soil with a pH below 6.0, apply a flowable limestone solution at a rate of 4 quarts per 100 gallons of water. This application can raise the soil pH by a full point if applied properly.
  2. Alternatively, you can use alkaline fertilizers such as 15-0-15 or 14-2-14 to help raise the soil pH. Apply these fertilizers according to the manufacturer’s instructions.

Home Remedies for Balancing Soil pH

  1. Wood ashes: Sprinkle a thin layer of wood ashes around the base of your Geranium macrorrhizum. Wood ashes contain calcium carbonate, which can help raise the soil pH. Be cautious not to apply too much, as excessive amounts can lead to nutrient imbalances.
  2. Eggshells: Crush dried eggshells into a fine powder and mix them into the soil around your Geranium macrorrhizum. Eggshells are rich in calcium carbonate and can gradually raise the soil pH over time.

Caring for Geranium Macrorrhizum After pH Adjustment

After applying the necessary amendments to balance the soil pH, it is essential to provide proper care for your Geranium macrorrhizum:

  1. Water the plant thoroughly after applying any amendments, ensuring that the soil is evenly moist but not waterlogged.
  2. Monitor the soil pH regularly, especially if you are using acid-forming fertilizers. Test the soil every 2-3 weeks and take action if the pH starts to drop below 5.8.
  3. Apply a balanced, slow-release fertilizer or compost in early spring when new growth appears. This will provide the necessary nutrients for healthy growth throughout the season.
  4. Maintain a consistent watering schedule, keeping the soil moist but not soggy. Geranium macrorrhizum prefers well-draining soil and can tolerate some drought once established.
See also  How to Balance pH for Cuphea Plants: A Comprehensive Guide

How Long Does pH Balancing Take?

The time required to balance the soil pH for Geranium macrorrhizum depends on the severity of the imbalance and the chosen amendment method. Chemical amendments, such as flowable limestone or alkaline fertilizers, can produce faster results, often within a few weeks. Home remedies, like wood ashes or eggshells, may take longer to take effect, as they release their pH-altering properties more gradually.

Consistently monitor the soil pH every 2-3 weeks and make adjustments as needed until the desired pH range is achieved. Once the pH is balanced, continue to test the soil regularly to ensure it remains within the optimal range for Geranium macrorrhizum.


Balancing the soil pH for Geranium macrorrhizum is crucial for its overall health, vigor, and appearance. By identifying pH issues, testing the soil, and applying the appropriate amendments, you can create the ideal growing environment for this beautiful perennial. With proper care and attention, your Geranium macrorrhizum will thrive and provide stunning blooms year after year.


  1. Cause of pH Drop in Geranium
  2. Low pH Symptoms Showing Up on Geraniums in Greenhouses
  3. Geranium Macrorrhizum Care
  4. Geranium Macrorrhizum Care Guide