Three Common Houseplant Pests

Bringing plants into your home is fun & exciting, but sometimes unwelcome guests hitch a ride with them. Outdoors, plants are in their element – their leaves get washed with the rain, the wind keeps the fine dust off, and pests have their natural predators. Houseplants may not have optimal sunlight, soil, water & humidity indoors, making them more prone to pests. Its important when bringing a new plant home, to check for any signs of infestation. If you notice something, treat the plant before adding it to your collection, to avoid risk of the other plants falling victim.

1. Mealybugs

These little guys can do irreparable damage to your plants. They are not always easy to spot but once noticeable, it can be too late. Mealybugs have a white fluffy appearance, but they’re definitely not cute. Mealybugs will attach themselves to the leaves and feed on the sap. If the infestation is wide spread, the plant wont be able to sustain itself, and you’ll eventually need to dispose of the plant.
There are however, ways to treat a Mealybug infestation, if you catch it in time.
1.1 Water
Take your plant outside and spray it with high pressure water, taking care not to damage the plant. Make sure you get under the leaves too – where they like to hide.

1.2 The good old fashioned finger trick Use your hands and inspect each leaf individually, squishing the bugs as you go along. Make sure to wipe off the leaf with a damp cloth afterwards. Wearing gloves is recommended, as these little guys are messy.

1.3 Control Ants
If you have ants in your home, you will more often than not, see them on plants that also have mealybugs. Why? Mealybugs secrete a substance called honeydew, which attract ants to the plant. Ants are also known pick up smaller bugs and transport them to nearby plants, spreading the infestation. In this case, take your plant outdoors and hose it down, removing the ants and the bugs. If the infestation is extensive, try the next step.

1.4 Liquid Dishsoap
Make the following mix in a spray bottle:
> 4 teaspoons of liquid dish soap
> 1 litre of tap water.
Spray solution directly on the plant, ensuring you cover all the mealybugs. Leave on for several hours, then rinse plant with fresh water. Repeat steps several times over a few days, if needed.

1.5 Alcohol
Dab a cotton bud in rubbing alcohol and apply to the mealybugs. Alcohol zaps and kills them directly. Repeat as often as needed.

1.6 Neem Oil
Neem oil is a newer, but highly effective method, in the treatment of house pests. Prepare as follows:
> 1/2tsp of neem oil
> 1/4 tsp dish soap (use natural options whenever possible)
> 0.5litre spray bottle – fill with tap water.
Mix all together and spray the mealybugs directly, then cover the rest of the plant. Only apply at night or in a dark room as sunlight will make the leaves more sensitive to light, causing burning. Apply weekly if needed & ensure not to increase the measurements as neem oil is highly concentrated.
Where can you buy neem oil in Mauritius? – MCAF

1.7 Natural insecticide spray
A more costly, but effective option is the No Bug Plus spray. Plant based and safe for both the environment and humans. Spray directly to plant on affected areas and root zone.
Apply once every week until mealy bugs are eradicated.

2. Spider Mites

Spider mites are so tiny but so destructive. These mites are actually not insects but are a part of the arachnid (spider) family. You’ll realise you have a spider mite problem when little webs appear on your plants leaves & stems, and light dots form on the leaves.
Spider mites feed, very similarly to mealy bugs, by sucking contents from leaf tissue, draining the plants of their food and energy. Spider mites are wind surfers, so keep your infected plants away from any draft that may spread them to other plants.
How to control and eradicate Spider Mites:

2.1 Water
As with mealy bugs, take your plant outside or in your shower, and spray your plant down. Using enough pressure to remove the mites, but not too much as to hurt your plant. This will break up the webbing, remove the eggs and wash off the mature mites. Keep the plant isolated from other plants while doing this to avoid possible spread.Repeat as often as necessary.

2.2. Neem oil
See instructions in 1.6.
2.3 Pepper & Soap Spray
> 6 tablespoons ground red pepper
> 6 drops of dish liquid
> 3 litres tap water
Mix in a spray bottle, and apply generously. Keep on for several hours, then rinse off. Repeat over several days as needed.

2.4 Pruning
Remove any heavily infested leaves or branches, and dispose of them correctly – not in your compost!

2.5 Plant care
Keep your plants well watered, fertilised and in optimal lighting, to avoid increased damage by the mites.

3. Scale

Scale are small disk-shaped insects that attach themselves to the upper and lower sides of leaves. Scale insects come in two groups: soft & hard shell, the latter being harder to get rid of, as insecticides or oils don’t always penetrate or get under the shell. Like spider mites, scale can crawl or blow from one plant to the next, so ‘quarantining’ a plant during treatment is important.
Here are some solutions:

3.1 Pruning
Remove any infected leaves if the scale infestation is too extensive. Dispose of properly.

3.2 Alcohol
Use a cotton swap and dab it directly on the scale. This works best for soft scale.

3.3. Neem oil
See instructions on 1.6

3.4 Tape method
I use this method the most. Take some masking tape, wrap it around your finger, and use your finger to stick and lift off the scale. This is highly effective but time consuming.

3.5 Natural insecticide spray
See 1.7 above

Whenever possible, use organic/natural pesticides.
Chemical pesticides should only be used as a last resort.

To help keep pests at bay, keep your plants in optimal condition by ensuring proper watering, adequate lighting and regular fertilisation.