If your Catnip turned brown and is dying the culprit is root rot. Powdery mildew is a fungal infection that is commonly seen in Catnip plants. Catnip plants will also die if there’s a severe infestation of Spider mites or Thrips.
Catnip plants are relatives of the mint plant. Catnips are also called Catswort and Catmint. Catnips are scientifically called ‘Nepeta cataria’.
Catnips are known for their herbal properties. Catnips can be used to make tea. Catnip flowers are used to treat cough.
Catnip leaves turning brown
Catnip leaves turn brown mainly due to root rot. If you see brown spots on your Catnip plant then it is due to Cercospora leaf blight disease.
Catnip root rot
Overwatering leads to waterlogged conditions around the Catnip plant. Waterlogged conditions rot the roots of the Catnip plant.
Various types of root rot may infect your Catnip plant but the root cause is overwatering. Make sure the soil is well-draining.
Roots become girdled when infected by root rot. Stems and leaves die as they don’t get adequate supply of water and nutrients.
Roots become brown, slimy and mushy. If you dig the plant out you can smell the rotten odor. The plant eventually becomes weak and the stem softens.
To prevent root rot in your Catnip plant spray copper fungicide in early spring.
How often should you water catnip?
Give your Catnip plant 200ml of water per 5 days. This should be enough provided the soil is well-draining and the pot has drainage holes.
Check the soil with fingers, do not let the soil go bone dry.
Brown spots in Catnip
Cercospora leaf blight is a fungal disease that is common in Catnip plants. Plant leaves are covered in small flecks that are surrounded by yellow halos.
These flecks eventually enlarge and turn brown. After this point the plant is as good as dead. Get rid of infected plants to prevent a large-scale infestation.
Dispose of the infected plant debris to keep this disease away from your garden.
Why is my Catnip yellow?
Catnip leaves turn yellow due to a disease called Bacterial leaf spot disease. Bacterial leaf spot disease is commonly seen in cold weather conditions. Spider mites infestation also causes leaves to turn yellow.
In a Catnip plant infected by Bacterial leaf spot disease, the leaves have spots that are surrounded by yellow halos.
These yellow-colored spots eventually turn black in color. Dispose of the plants that are severely infected and keep the area clean of any debris.
White spots on Catnip leaves
White spots on Catnip leaves are an early sign of Spider mite infestation. Presence of spider mites can be confirmed if you see webcasts in the leaves of your Catnip plant.
Spider mites are tiny insects that feed on the plant sap. These pests inject toxins into the plant while they suck plant sap.
This causes white spots on the leaves of Catnip. Eventually leaves of the infested plant become dry and turn yellow in color.
You can get rid of spider mites by spraying water forcefully at the infested branch. You can also spray insecticidal soap for better results.
If the infestation is severe spray Neem oil on the infested plant/branches. Do not spray Neem oil/Insecticidal soap when you see beneficial insects on the plant.
Catnip leaves curling
Catnip leaves curl when the plant doesn’t get adequate water. Are your Catnip leaves dry and curly? Then it’s probably underwatered.
Always remember that your potted plants require more water than those in your garden. Make sure the pot has drainage holes.
Check the soil with fingers and water when it is dry up to an inch or two. Do not let the potting mix go bone dry.
If it’s summer increase the watering frequency to prevent dehydration.
Catnip leaves turning red
Catnip leaves lose their green color and turn red when the plant can’t produce chlorophyll. This happens due to various reasons.
A lack of Nitrogen/Phosphorous causes the lack of chlorophyll in Catnip. The purplish color of the Catnip leaves is due to a pigment called Anthocyanin.
Anthocyanin pigment replaces Chlorophyll in the Catnip leaves. You need to amend the soil when you notice such signs.
Amend your soil by adding some humus with composted manure to it. Catnip leaves will turn green soon.
Are coffee grounds good for Catnip?
Yes, coffee grounds are good for Catnip plants. They increase the acidity in the potting mix. This means they enhance nutrient absorption in Catnip plants.
Can Catnip get moldy?
Yes, Catnip plants can get moldy when they are infected by fungus. The most common fungal disease in Catnip plants is Powdery mildew.
Powdery mildew on Catnip
Powdery mildew is a fungal disease that infects the plants when the leaves are moist for a long time. Leaves get covered in a layer of powdery mold, that’s why it’s named so.
White, powdery fungal growth can be seen on the leaves, petioles and stems. Symptoms first show on older leaves, shaded leaves and undersides of the leaves.
Infected plants shrivel and die. Plant becomes stunted and senesces early. Make sure your Catnip has good ventilation.
Powdery mildew control in Catnip
- Do not wet the leaves of your Catnip and make sure there’s good air circulation around the plant.
- Trim your Catnip with a pair of pruning shears to prevent diseases.
- Spray Chamomile tea on the infected plant/plant parts, trust me, it does wonders!
- Mix 1tsp. Murphy’s Oil Soap and a tsp. baking soda in a quart of water. Spray this solution on an infected plant.
Tiny black bugs on Catnip
Those tiny black bugs you see on Catnip are ‘Thrips’. Thrips have elongated bodies with two horns at the front. Thrips suck the plant juice from Catnip plants using their sharp mouthparts.
Leaf stippling is the main symptom of a thrip infestation. Place a white sheet of paper under the infested branches and shake them.
If you see thrips it’s time to get rid of them. Thrips leave silvery streaks on the leaves of your Catnip plant.
Control thrips on Catnip
- Hang blue sticky traps around your Catnip plant to control thrip populations.
- Spray an insecticide if there’s a severe thrip infestation. Pyrethrin or other types of oil-based spray works wonders to get rid of thrips.
- Introduce Ladybugs, Lacewings and Minute pirate bugs into the infested Catnip plant to control thrips biologically.
Happy Gardening 🙂