Indoor Plant Pests and Solutions

Spider Mite Damage to an Oxalis Iron Cross

Pests! They are a part of life, and unfortunately a part of owning Indoor Plants. There is much speculation that to have pests means you as a plant owner are doing something wrong and you need to change the way you look after your plants to be pest free. Unfortunately, this is a myth and if you have Indoor Plants, then at some point you will have pests. 

Spider Mite Webs and Eggs

The same as any living thing, there is no way to avoid issues forever. Just like humans will pick viruses up eventually, plants will pick up annoying bugs. However, there are ways to minimise the chance of large-scale infestation and to treat your precious plants. We are going to take a look at some of the most common pests to Indoor Plants and what you can do to discourage them, treat an infestation and return your plants to a happy healthy state.

Fungus Gnats - Image by Heeman’s

Gnats

Fungus Gnats are possibly the most common and annoying pest that frequents a home. They are a small black fly type of bug that will dig into soil and breed. They can proliferate very quickly, especially in the warmer months, and have a very fast-breeding cycle. Gnats are tiny and attracted to damp environments and Carbon Dioxide. It’s why they will try to fly in your nose or mouth, the perfect damp and CO2-rich environment! Plants, even if a dryer variety, absorb CO2 meaning the gnats are attracted to them and from quite a distance. Being so small, they can come in under doors, through ventilation, through open windows, or any tiny crack in a living space. They will seek out the source of the CO2 and begin to breed in the soil. They feed on decaying biological matter, however, in a bad case, can also attack a plant’s root system for food. Often the advice given is that letting the soil dry out will solve the issue, however, this is not the case. Gnat larvae will become dormant in the soil and after a water of the plant, they start breeding all over again. This is why a fresh bag potting mix can lead to an infestation very quickly. It can be filled with larvae. Peat Moss arrives sterile, so that particular problem is avoided, however once opened and exposed to moisture and then plants and biological materials, Gnats are just as possible as they are in every other potting medium. Changing all the soil over to sterile peat can help, but treatment will still be needed to break the lifecycle of the gnats. If you are willing to wait and have a small indoor plant collection, sticky strips or carnivorous plants will eat up the adults, halting the breeding cycle. This is a completely natural way to eventually rid your home of the little black annoyance. However topical sprays are also available. PLEASE NOTE: Sticky traps must ONLY be used indoors. Anything will stick to these traps including good bugs, small birds, and rodents. Using them outside can inadvertently kill beneficial bugs and small creatures.

Mealybug

Mealybug

This little guy is a real pain. He likes to hide deep in the crevices of plants and start a nest meaning evicting him can be tricky. Mealy is a little white bug and leaves a cotton-like white residue that looks a bit like mould on the stems of plants. It can be a tricky pest to realise you have until a whole colony has set up shop as they tend to stick to crevices in stems, however, with regular checks, you will be able to see the beginnings of an infestation and treat it fast. There is no way to prevent Mealybug from occurring. They are common in the warmer months and, although unknowingly introducing a plant with Mealy without treatment can start an infestation, they can occur randomly. They can be hiding on plant materials, pots, tools and other plant items we bring into our homes. They can occur when you put an indoor plant outdoors for sun, rain, repotting etc. There is no way to prevent them, however, regular inspection of your plants will catch them out early. They can then be wiped off the plant with a wet cloth quite easily. If they have set up a nest, however, treatment is the best option. One treatment is all that is needed however if the nest is missed in the treatment, a second application will be required. Treatments often also work with other pests like Aphids, Scale and White Fly. Aphids are green in colour and will leave little yellow marks on leaves where they have bitten the plant. Scale will look like little scabs up and down the stem and White Fly will cover the leaves and are little White Flying insects. Edible and Outdoor plants should not be sprayed as treatment can kill good insects like Bees. It is also important to note that one species of Ladybug has a larva that looks very much like a Mealybug. It is larger and more cotton looking and it will in fact eat Mealybug. Therefore is you have both on your plant, leaving it alone will ensure lots of food for the Ladybug and, eventually, no more Mealybug!

“There is simply no way to prevent ever having pests. Owning plants equals sometimes owning pests but with proper advice and a good treatment product, you and your plants can live together in harmony. ”

Spider Mite

Spider Mite - Image by Gardening Heavn

The tiny and ever destructive Spider Mite is very common in Warmer months, especially Spring, and occurs in most plant homes where one of the Spider mites favourite eating plants resides. Like all pests, Spider Mite have their favourite foods and are commonly found on Calathea, Oxalis, Alocasia and many many more.  These tiny pests will travel easily on warm Spring breeze so find their way into homes without issue. Once they have found a plant they will quickly breed, laying eggs on the underside of leaves. They have tiny webs which are often a good and clear sign of infestation, however, as small spiders can also live in plants, the most common sign is speckled leaves. If you turn the leaf over you can often see tiny little tan bugs crawling around amongst the eggs. The Spider Mite will cause the leaves to almost drain of colour giving it a mottled look, and the leaves will then start to brown and curl before dying. Treatment is the best and most efficient way of removing Spider Mite before the plant succumbs to them. Wiping leaves with Neem Oil can help however if it is not the correct potency, for example, a ‘Leaf Shine’ Neem Oil, and is not strong enough the Mites will not be removed, just subdued until they can increase numbers. Pest Spay targeted to these annoying little bugs acts quickly when the foliage is sprayed and the Mites will be removed with one to two applications. The plant will then recover with its new growth, however, the damaged leaves will retain their damage and may need to be removed.

‘Mealybug Destroyer ‘Ladybug Larva and Mealybugs - Image by Vanessa Marie

One of the most common ways pests are introduced is by putting plants outside for ‘some sun’ or ‘because it was raining’. Leaving your indoor plant in the outdoors leaves it open to all pests passing by on the land, other plants, breeze and rain. There is no need to put an indoor plant outside, ever. They have been grown from the beginning, in most cases, indoors in a Greenhouse Environment. They have adapted to such an environment and do not require direct light or breeze or rain. To do so you don’t just risk pests, you also risk plant shock, burning, ‘cooking’ the plant, dust and dirt on the leaves from the rain, overwatering and even just forgetting about the plant until it's too late. Once you find a spot in your home where your indoor plant is happy, it can stay there happily. Large plants can easily be watered in showers and baths where you can control the water, leave them to drain, and not risk damage or pests.

It is important with all of these pest treatments and minimising ideas to remember that it won’t stop new infestations in future. Just like having a cold won’t prevent another down the line, your living breathing plant will have many issues over its lifetime. There is simply no way to prevent ever having pests. Owning plants equals sometimes owning pests but with proper advice and a good treatment product, you and your plants can live together in harmony. 

Happy Growing!