Ajuga is a low-maintenance plant that does not require heavy fertilization or care. However, fertilization can help a Ajuga plant grow healthier and stronger. It is recommended to fertilize Ajuga plants in the spring and fall seasons. Before applying any fertilizer, it is important to test the soil to determine the nutrient levels and pH. Ajuga prefers slightly acidic soil with a pH range of 5.5 to 6.5. A balanced fertilizer with a ratio of 10-10-10 or 12-12-12 can be used for Ajuga. The fertilizer should be applied lightly, following the package instructions. Over-fertilizing can lead to excessive growth, which can be detrimental to Ajuga. It is also important to water the plants well before and after fertilization. Watering before fertilization makes the soil moist and helps the fertilizer in absorbing. Watering after fertilization washes off any fertilizer that may have accidentally gotten onto foliage or flowers. In summary, Ajuga plants can benefit from light fertilization with a balanced fertilizer twice a year, in spring and fall. Always follow the package instructions and avoid over-fertilizing.