Aleyrodidae ssp. Copyright: Gardening Know How
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Describing the appearance of Whitefly is self-explanatory. Along with the small, angel-like flies hovering around an unfortunate plant, small eggs will be littered over the leaves and stems. Remove the affected plants out of the house and away from other specimens to avoid the problem spreading. Always check neighbouring plants for the infestation, too.
Infestations will be located in the nooks and crannies of wooded stems, flowers and both sides of the leaves.
Plants - Most specimens can be affected by Whitefly, with most vulnerable being Dracaena, Ficus, Monstera, Palms, Umbrella Trees & Yuccas.
1. Prepare a room (ideally small) where there aren't any airborne Whitefly or plants present. Providing a 'neutral' zone where you can confidently say that there aren't bugs will strengthen the pest-regulation. Keep the doors shut and regularly check for any critters that may be hovering around the windows or lampshades before the affected plants enter.
2. Cut off the affected areas or flower stalks - if you can't remove them for whatever reason, rub your fingers across the affected areas to destroy the eggs and larvae. Spend some time with this step - the eggs can be housed pretty strongly onto the plant, meaning that the hose may not eradicate all of them.
3. Take the plant outside and GENTLY wash the stem, leaves and each cubbyhole using an outdoor hose. It's important to spray in at least three different angles to ensure thorough administration.
4. While the plant is drying-off, remove the top quarter of the soil in favour of a fresh batch of the appropriate potting-mix - cactus compost for succulents, tropical plants for houseplant compost, etc. This is to remove any fallen larvae of flies that may be hiding in the potting mix.
5. Perform a final hose-down before placing it in a warm room, away from other specimens to dry-off. If the temperature is above 15℃ (59℉), keep it outside so that natural predators, like ladybirds and green lacewings, can have a go at the critters, too.
6. Once the specimen is bone-dry, it's time to administer a pesticide. Although there is a choice between two options (organic or chemical-based sprays), ukhouseplants would highly recommend using the latter option, due to the pest's ability to bypass organic varieties.
(Step 7 follows after the Pesticide Options)
Neem Oil is used across the world, and for a good reason. Not only is it accessible in many stores, but it'll also get to work after the first application. Dilute the liquid, (to the manufacturer's recommended strength) with water and/or dish soap and spray thoroughly onto the foliage and its cubbyholes. Any flowers must be removed instead of misted, due to the heightened chance of another infestation lurking in the background.
Insecticidal or Horticultural Soap is another popular pesticide on the market, and there are three versions to consider. The first way is by purchasing an RTU (ready-to-use) spray bottle, which can be immediately used on the plants. Although most garden centres will stock this, it's far more economical to purchase the second option - concentrated bottles. This method comes with pro's and con's but is far cheaper to use if you have multiple infestations. It's self-explanatory and highly beneficial for the outbreak as long as you use the correct levels of dilution - the only downside is its availability in local centres. It's best to buy this option online as there are many different companies to choose from, with some being cheaper than others. The final and most economical way is by making it yourself;
There are three ingredients in creating your own insecticidal soap - a vegetable, tree or nut-based oil, non-fragrant dishwashing soap and tap water. Most oils are acceptable, with the most successful being vegetable, sunflower, neem and olive oil. Add two parts oil, one part dishwashing soap and eight parts water to create the dilution. Although it's best to fresh bottled water, tap water that has been allowed to sit for 24hrs will also be fine. Spray the dilution thoroughly around the plant, empathising both the infestations and the potential-hit areas. This method must be performed weekly over a month or two, along with regular pest inspections - as soon as you see a bug, crush it!
Diatomaceous Earth (D.E. or DE) is grounded diatom mantels (skeletons) that can be highly abrasive to many arthropods, including Whitefly. Although the white powder may be soft to the human touch, the sharp tooth-like edges off each grain will begin to cut its way into the pests' eco-skeleton, causing significant discomfort and weakened health. After a period of several days, the infestation will decrease as the mature mothers won't be able sufficiently to lay her eggs. Usually, DE is applied as a thin layer across the foliage of outdoor plants, which will work until there is a rainstorm; however, you'll have to change the method of application to eradicate indoor pests. Instead of using powder to combat your infestation, mix the DE with water to create a more efficient solution to access the plant's cubbyholes and hard-to-reach areas. Add one tablespoon of DE to 500ml of water (0.11 imperial pints) and mix well. Finely mist both sides of the leaves and its stems so that the plant is covered in a thin film, which will begin its work within twenty-four hours once dry. Its eggs may be immune to the pesticide, so it's important to perform another fine spray seven days later to attack to the recently-hatched larvae. As you have followed the first seven steps mentioned in the previous section, you shouldn't see any signs of an infestation for several weeks. We'd recommend waiting six weeks before deeming the specimen pest-free, as relapses of later-hatching larvae could occur. If pests do return, follow the seven steps mentioned above, along with the misting of its foliage with this solution. If the infestation is large, you may wish instead to opt for a chemical-based pesticide to destroy the infestation more effectively. DE is considered safe to both pets and humans and has no links to the development of illness or cancers.
ukhouseplants would recommend using 'Bayer Garden Provado Ultimate Fruit and Vegetable Bug Killer Concentrate', as it worked IMMEDIATELY after one application. It's a concentrated product, meaning that you'll have to dilute it with the appropriate amount of water. Spray both sides of the leaves, along with any cubbyholes that could house the infestation. Repeat this step weekly for the next month to aid the destruction of the pest.
Permethrin - Pesticides that contain this chemical will also work wonders after the first use. Whitefly has been proven to respond well to this chemical, immediately showing signs of a decline after a few hours. The only down is the price - even though you can only find this product online, the cost (with delivery added) is high compared to the first option. If you have a significant infestation, it's probably best to go down the Permethrin route, but anything smaller wouldn't warrant such an expensive bottle. Click here to shop around for Permethrin.
7. Once the pesticide has been administered, locate all of the affected plants into the prepared room. Keep them here for at least a week to check if the infestation continues. Inspect all of the plants along with any windows or lights (Whitefly like light-sources).
8. Open all of the windows in the house (not just the quarantined room) for an hour to allow redundant flies to escape unhurt. It's far easier to let them fly away than attacking each fly individually, as this will take AGES. Get a handheld hoover and suck each airborne pest that you crosses your path, once the windows are shut again. Keep an eye out around the home for the next few days, checking the hard-hit areas of windows and lampshades.
9. After a week of quarantine, inspect the plants for any sign of an infestation. Once there are no more visible pests in the whole house, you can safely re-introduce them back into their original locations.
10. Always keep an eye out for more Whiteflies in the oncoming weeks. Kill or hoover each one that you come across - this can be a long process to eradicate, so doing small hunts each day will make a big difference in the long term!
N. B. - Although you should perform the wiping and hosing-down process BEFORE each pesticide application, you can wash the foliage at any given time to keep the infestation under control.
At the local plant shop or garden centre, regulate and inspect any plants that you wish to buy. Check around the hard-hit areas, for instance, the foliage and stems, before considering the purchase. Most Whitefly infestations come from already-affected plants, so always keep this in mind when increasing your plant-collection!
Change the top layer of the soil when bringing any new plant from a shop. Replacing the top layer of the compost will remove any larvae that may have fallen in, or been deposited by a pest.
Regularly check for pests on your own plants. Although this may sound patronising, many gardeners forget to inspect their indoor specimens. As soon as you see a symptom, keep it quarantined and follow the steps above!
For any more questions or queries about Whitefly, be sure to message us via this link or comment in the section below!
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