Pasquesi Blog

Melinda's Gardening How-To: Managing Pests on Indoor Plants

Melinda's Gardening How-To: Managing Pests on Indoor Plants

Are your plants healthy? You may notice some yellowing, spotting or speckling on the leaves or a few insects that have taken up residence on your favorite indoor plant. Don't despair. Instead, invest a bit of time and effort managing these problems and keeping your plants looking their best. 

 

Common Symptoms, Possible Causes and Solutions

Yellow leaves  

CAUSE: Too much or not enough water is the most common reason. 

SOLUTION: Water thoroughly and as recommended on the plant tag. Watering frequency will vary with the type of plant, potting mix used, indoor temperature, humidity and light. 

   *Move plants to a container with drainage holes if needed. 

   *Pour off excess water that collects in the saucer or make your job easier and improve plant growth with a humidity tray.

 

Edges of Leaves turn brown 

CAUSE: Not enough water, root rot from overwatering, over fertilization, fluoride in water, salts in softened water. 

SOLUTION: Adjust watering as needed (see above). Only fertilize actively growing plants with a dilute solution of houseplant fertilizer. This is usually March through November unless you're growing plants under artificial lights or in very high light conditions. Use rain water or water collected from dehumidifier that has not been cleaned with toxic chemicals to avoid fluoride and salt damage.  

 

Spots on leaves  

CAUSE: Fungal or Bacterial disease. 

SOLUTION: Remove infected leaves and stems. Adjust watering. This is often enough to restore plant's health allowing it to overcome the disease. Avoid water on the foliage and drafts of hot and cold air while providing enough space for adequate airflow around each plant.

 

Common Insect Pests, their symptoms and control 

Fungus gnats  

IDENTIFY: These annoying insects are often mistaken for tiny fruit flies as they flit around the house. They feed on organic matter in the soil and are more annoying to us than harmful to the plants. 

CONTROL:  Allow the potting mix to go slightly drier than normal.

   *Use Summit Mosquito Bits® labeled for fungus gnat control. Sprinkle this product on the soil surface or mix with potting mix prior to planting. The active ingredient is Bacillus thuringiensis israelensis. This naturally occurring bacterium only kills larvae of fungus gnats, black flies and mosquitoes. It's safe for people & pets. 

   *And always be sure to read and follow label directions whether using natural or synthetic pesticides. 

 

Aphids 

IDENTIFY: These small tear drop shaped insects suck plant juices causing the leaves to yellow, brown, wilt or become distorted. They secrete a clear sticky substance known as honeydew. 

CONTROL: *Place plants in the sink or tub and knock the insects off the plant with a strong blast of water.    

   *Follow with several applications of insecticidal soap, NEEM or horticulture oil labeled for use on houseplants. Repeat applications may be needed. These are safe for pets and people. 

   *Bonide systemic houseplant insect control is applied to the soil, absorbed by the plant and provides weeks of control. It also contains fertilizer. Keep treated plants out of the reach of pets and children that like to graze on your indoor plants.  

   *And always be sure to read and follow label directions whether using natural or synthetic pesticides. 

 

Mites 

IDENTIFY: These tiny pests are relatives of spiders. Most gardeners notice the damage before spotting the tiny pests that require a hand lens to see. Damage includes a speckling of the leaves, yellowing and browning. These pests also secrete the clear sticky substance called honeydew. Shake a leaf over a white piece of paper for easier detection. 

CONTROL: Same as aphids. Repeat applications are usually needed. 

 

Scale 

IDENTIFY: Hard bumps that can be scraped off the stems and leaves. These insects also secrete honeydew. 

CONTROL: Start by gently removing the hard-shelled adult scale using your fingernail or old toothbrush. Then treat the nearly invisible clear nymphs (immature stage of scale) as you would aphids. Persistence is key to success. Continue to monitor, control the adults as they appear and treat the clear immature scale.  

 

Mealybugs 

IDENTIFY: Cottony masses on stems, leaves and area where the leaves join the stem are usually a soft scale known as mealybugs. They suck plant juices and secrete honeydew. 

CONTROL: Start by dissolving the cottony cover and killing the insects and eggs below. Touch each cottony mass with a cotton swab dipped in alcohol. Then treat the clear nymphs (immature stage of mealybugs) as you would aphids.  

 

Whitefly 

IDENTIFY: Clouds of tiny white fly-like insects can be found resting on your plants. Shake a stem and watch them fly away. They cause similar damage as aphids and mites.   

CONTROL: Yellow sticky traps can help reduce populations and subsequent damage to the plants. Follow recommendations under aphids if greater control is desired. Persistence is essential for controlling with pest.

 

Written by gardening expert, Melinda Myers. Melinda Myers is a nationally recognized gardening expert with more than 30 years of horticulture experience. She is a wealth of knowledge and we are pleased to share Melinda’s Gardening How-To with you!

You've packed away the holiday decorations, rearranged the furniture and finally have time to focus on your indoor plants. You may notice some yellowing, spotting or speckling on the leaves or a few insects that have taken up residence on your favorite indoor plant. Don't despair. Instead, invest a bit of time and effort managing these problems and keeping your plants looking their best. 

Common Symptoms, Possible Causes and Solutions

* Yellow leaves  
CAUSE: Too much or not enough water is the most common reason. 
SOLUTION: Water thoroughly and as recommended on the plant tag. Watering frequency will vary with the type of plant, potting mix used, indoor temperature, humidity and light. 
   *Move plants to a container with drainage holes if needed. 
   *Pour off excess water that collects in the saucer or make your job easier and improve plant growth with a humidity tray.

* Edges of Leaves turn brown 
CAUSE: Not enough water, root rot from overwatering, over fertilization, fluoride in water, salts in softened water. 
SOLUTION: Adjust watering as needed (see above). Only fertilize actively growing plants with a dilute solution of houseplant fertilizer. This is usually March through November unless you're growing plants under artificial lights or in very high light conditions. Use rain water or water collected from dehumidifier that has not been cleaned with toxic chemicals to avoid fluoride and salt damage.  

* Spots on leaves  
CAUSE: Fungal or Bacterial disease. 
SOLUTION: Remove infected leaves and stems. Adjust watering. This is often enough to restore plant's health allowing it to overcome the disease. Avoid water on the foliage and drafts of hot and cold air while providing enough space for adequate airflow around each plant.

Common Insect Pests, their symptoms and control 
* Fungus gnats  
IDENTIFY: These annoying insects are often mistaken for tiny fruit flies as they flit around the house. They feed on organic matter in the soil and are more annoying to us than harmful to the plants. 
CONTROL:  
   *Allow the potting mix to go slightly drier than normal.  
   *Use Summit Mosquito Bits® labeled for fungus gnat control. Sprinkle this product on the soil surface or mix with potting mix prior to planting. The active ingredient is Bacillus thuringiensis israelensis. This naturally occurring bacterium only kills larvae of fungus gnats, black flies and mosquitoes. It's safe for people & pets. 
   *And always be sure to read and follow label directions whether using natural or synthetic pesticides. 

* Aphids 
IDENTIFY: These small tear drop shaped insects suck plant juices causing the leaves to yellow, brown, wilt or become distorted. They secrete a clear sticky substance known as honeydew. 
CONTROL:  
   *Place plants in the sink or tub and knock the insects off the plant with a strong blast of water.  
   *Follow with several applications of insecticidal soap, NEEM or horticulture oil labeled for use on houseplants. Repeat applications may be needed. These are safe for pets and people. 
   *Bonide systemic houseplant insect control is applied to the soil, absorbed by the plant and provides weeks of control. It also contains fertilizer. Keep treated plants out of the reach of pets and children that like to graze on your indoor plants.  
   *And always be sure to read and follow label directions whether using natural or synthetic pesticides. 

* Mites 
IDENTIFY: These tiny pests are relatives of spiders. Most gardeners notice the damage before spotting the tiny pests that require a hand lens to see. Damage includes a speckling of the leaves, yellowing and browning. These pests also secrete the clear sticky substance called honeydew. Shake a leaf over a white piece of paper for easier detection. 
CONTROL: Same as aphids. Repeat applications are usually needed. 

* Scale 
IDENTIFY: Hard bumps that can be scraped off the stems and leaves. These insects also secrete honeydew. 
CONTROL: Start by gently removing the hard-shelled adult scale using your fingernail or old toothbrush. Then treat the nearly invisible clear nymphs (immature stage of scale) as you would aphids. Persistence is key to success. Continue to monitor, control the adults as they appear and treat the clear immature scale.  

* Mealybugs 
IDENTIFY: Cottony masses on stems, leaves and area where the leaves join the stem are usually a soft scale known as mealybugs. They suck plant juices and secrete honeydew. 
CONTROL: Start by dissolving the cottony cover and killing the insects and eggs below. Touch each cottony mass with a cotton swab dipped in alcohol. Then treat the clear nymphs (immature stage of mealybugs) as you would aphids.  

* Whitefly 
IDENTIFY: Clouds of tiny white fly-like insects can be found resting on your plants. Shake a stem and watch them fly away. They cause similar damage as aphids and mites.   
CONTROL: Yellow sticky traps can help reduce populations and subsequent damage to the plants. Follow recommendations under aphids if greater control is desired. Persistence is essential for controlling with pest.

Written by gardening expert, Melinda Myers. Melinda Myers is a nationally recognized gardening expert with more than 30 years of horticulture experience. She is a wealth of knowledge and we are pleased to share Melinda's Gardening How-To with you!