Is Your Rosemary Struggling? Find Out How to Revive It!

Rosemary, the beloved aromatic perennial herb, is known for its hardy nature. If your rosemary plant is showing signs of stress, it’s crucial to identify the problem and take appropriate action to revive it. In this article, we’ll explore common reasons why rosemary plants struggle and provide solutions to get them back to good health.


1. Too Much Water

Overwatering can lead to the drowning of rosemary roots, resulting in browning of the leaves’ tips. Contrary to popular belief, when leaves turn brown, giving the plant more water worsens the problem. To fix this, stop watering the plant and let the soil dry out completely before watering again. Ensure proper drainage for the plant’s location, or consider moving it to a spot with better drainage. For potted rosemary, allow the soil to dry out between waterings and ensure proper drainage through the pot’s holes.


2. Insufficient Water

Underwatering can also cause brown leaves, making the plant appear twiggy and dry. To remedy this, provide a good soak of water to the plant and remove any brown, dry areas. Additionally, feed the roots with a liquid seaweed fertilizer to aid in the plant’s recovery.


3. Improper Soil

Heavy clay soil is unsuitable for rosemary, as it can lead to waterlogging and root rot. It also compacts easily, hindering oxygen reach to the roots. To address this issue, add organic matter or coarse sand to the soil before planting to improve drainage. If the plant is already in heavy clay soil, consider replanting it in pots or raised beds with well-amended, lighter soil. Rosemary prefers poor, chalky, stony, and sandy soil types but can tolerate most soils except for heavy clay.

Further reading:  The Beauty of Purple Leaf Sandcherry: A Colorful Addition to Modern Gardens


4. pH Imbalance

Rosemary thrives in slightly acidic to neutral soil, with a pH between 6.0 and 7.0. If the soil is too acidic, the plant may turn yellow and decline. Test the soil’s pH using a soil test probe and make necessary adjustments to bring it within the preferred range.


5. Inadequate Sunlight

Rosemary requires full sun to thrive. Insufficient sunlight can impede soil drying and lead to problems associated with overwatering. If the foliage starts to yellow, it may be a sign of too much shade. Consider relocating the plant to a sunnier spot. Ideally, rosemary needs at least 6 hours of sunlight daily, preferably 8 hours.


6. Unsuitable Temperatures

Rosemary enjoys mild winters and dislikes frost. Cold and wet soil can quickly lead to root rot and plant decline. If temperatures regularly drop below 30°F in your area, consider growing rosemary in containers on a sheltered patio or bring it indoors during winter. Rosemary prefers temperatures between 55°F and 80°F.


7. Excessive Humidity

Rosemary naturally grows in coastal areas with moderate humidity and good airflow. High humidity can inhibit evaporation, leading to fungal diseases and root rot. Ensure adequate air circulation around the plants and trim them if necessary. Maintain humidity levels at around 45% – 55% for optimal growth.

beach rosemary

8. Root Rot

Root rot occurs when the plant’s roots are surrounded by excessive water, leading to fungal infection. If you notice browning, drooping, or wilting sections of the plant, adjust your watering schedule immediately. In severe cases, it’s best to remove the affected plant to prevent the spread of the infection. If caught early, cut off the damaged roots and repot the plant in fresh, well-draining soil. Commercial fungicides may also be used to treat the affected areas.

Further reading:  The Ultimate Guide to Fertilizing Snake Plants

potted rosemary

9. Pest Infestation

Although not common, rosemary can attract pests like aphids, spider mites, whiteflies, and spittlebugs when under stress. Control these pests promptly if you notice dry foliage or signs of infestation. Washing the pests off the plant can help control minor infections. Alternatively, treat with neem oil or an insecticidal soap. Monitor the plants closely to prevent further infestations.


10. Powdery Mildew

Powdery mildew, a fungal infection, can impact rosemary plants with poor air circulation, excessive shade, water, or incorrect temperatures. Watch out for powdery white or gray growth on the leaves, stems, and flowers. Although it won’t kill the plant, powdery mildew can lead to curling, yellowing leaves, leaf drop, and malformed flowers. To manage this issue, remove infected parts, improve sun exposure, enhance air circulation, and water at ground level. Commercial fungicides may be used but require multiple applications for effective eradication.

powdery mildew

11. Lack of Pruning

While rosemary can survive without regular pruning, pruning can enhance air circulation and prevent pest and disease issues. It also makes the plant more manageable and can shape it into a hedge. Consider pruning out branches to improve air circulation.


12. Excessive Pruning

Avoid pruning rosemary within 6-8 weeks before the average frost date in your area. Pruning at the wrong time or excessively can harm the plant, potentially leading to irreparable damage. When pruning in late winter or early spring, ensure you leave some foliage on the stems and avoid cutting beyond the older woody stems. Fertilize after pruning to support new growth.

Further reading:  CONJUGATED LINOLEIC ACID (CLA) - Uses, Side Effects, and More


13. Nutrient Imbalance

Although rare, a lack of nitrogen can cause yellowing leaves. To address this, feed the plant with a nitrogen-rich fertilizer. On the other hand, excessive nitrogen can lead to drooping leaves and vigorous but susceptible growth. In such cases, flush the soil and withhold fertilization for a while.


14. Incorrect Fertilization

While rosemary thrives in sandy, chalky soil, it benefits from additional feeding. Apply a general fertilizer during the growing season and avoid fertilizing in winter. Underfertilization can lead to pale, yellow leaves, while overfertilization may cause stunted growth and leaf discoloration. Follow the instructions on the fertilizer packaging and adjust accordingly.

coffee grounds

15. Overcrowding

Rosemary plants do not appreciate overcrowding. When planted too close together, they compete for root space, limiting access to nutrients and water. Remove any plants that are too close and provide adequate air circulation. If growing a rosemary hedge, space the plants 18-24 inches apart and ensure regular pruning for better airflow.

rosemary hedge

16. Limited Pot Space

Pot-bound rosemary plants may exhibit lackluster growth and yellowing lower leaves. If the roots appear crowded and tangled around the pot’s edge, it’s time to repot the plant into a larger container with fresh potting soil. Gently tease the roots to prevent them from growing in circles.

pot-bound rosemary

By understanding the potential issues and implementing the appropriate solutions, you can ensure your rosemary plants stay healthy throughout the year. Keep a close eye on your plants, and address any signs of struggle promptly to help them thrive.

Read Next: 6 Reasons Why Your Lavender Is Dying (& How To Fix It)