Aphids on tomatoes – causes and control

Tomatoes are threatened by numerous diseases. Pests also like to attack them, especially aphids. Young plants in particular are threatened. After pricking they are a little weakened, which the pests like to take advantage of and finally fall on the tender little plants. Aphid infestation can result in leaf blisters, stunted leaves, rolled leaves, yellow spots, stunted growth and curvature of the shoot tips. The flowers also often do not develop satisfactorily. Aphids also excrete honeydew, which in turn attracts ants. This honeydew also serves as food for soot mushrooms. When these settle, they cover the plant with an unsightly black layer, which impairs the tomato plant’s breathing and growth. But worst of all is that aphids spread viral diseases among plants. The flying specimens are therefore particularly dangerous. So you really don’t want aphids on tomatoes. Nobody needs them.

Causes of aphid infestation in tomatoes

I’ve read many times that the best remedy for aphids is prevention. Healthy plants have enough protective mechanisms to be able to defend themselves against the infestation. I disagree with that. Firstly, tomato plants have very high demands, which can usually not be met 100 percent, and secondly, you have no influence on the weather and humidity.

Aphids love tomatoes, especially young plants, and just love to pounce on them. You are usually powerless against this, regardless of whether the plants are in the greenhouse or outdoors. It happens from time to time that the pests spread. With larger plants outdoors, there are usually fewer problems.

Tomato plants are not extremely susceptible to infestation. If the pests are discovered in good time, simply rinsing off is usually sufficient. When cultivated in a greenhouse, pests with leaf suckers are significantly more common. It’s because of the stagnant air. If you change something, the lice usually disappear very quickly.

One cannot speak of causes in general. Often it is mistakes in care that weaken the tomato plants. Aphids prefer weakened plants. So if a plant is not quite fit, then it is twice as bad off. There can be several reasons why she is not doing so well.

• Wrong location
• Bad, unsuitable substrate
• Too much or too little water (also from above)
• Too much, too little or the wrong fertilizer
• Not enough light
• Drafts
• Standing air (greenhouse)
• cold
• Heat…

So there are many causes. One alone usually does not cause much damage, but when several factors come together, the plant is weakened and it usually does not take long for the first aphids to settle.

Prevent aphids

Reliable prevention is not possible. You can’t 100 percent prevent aphids from spreading to tomatoes. However, prevention is extremely important. Strong and healthy plants are really not that often attacked by pests and also by diseases. If aphids settle in spite of everything, it is important to spot them as quickly as possible and to do something about them right away.

• Plant tomato plants at a sufficiently large distance. Air must be able to circulate between them. Sufficient ventilation must be provided for greenhouse cultivation, ideally intermittent ventilation.
• In fact, dry air is bad for plants and good for aphids. It is therefore advisable to shower the plants regularly. In the case of tomatoes, however, this is anything but good. Here it is better to let it, at least not spray it on the plants themselves, as much as possible around them.
• Promote natural enemies – they include ladybugs, earwigs, lacewings, and parasitic wasps. By providing these insects with food and shelter, you are already making a contribution to aphid prevention and control.
• It is important to fertilize properly, overfertilized tomato plants are prone to pests, just like those with a lack of nutrients. Artificial fertilizers contain a lot of nitrogen and it attracts aphids and other pests. I would only use natural fertilizers for tomatoes anyway. You don’t want to eat chemistry.
• Aphids like to overwinter on trees and dead plant parts. So you have to remove harvest residues thoroughly and cut back the trees vigorously in spring. For most of them, a cut is cheap anyway.
• Inject plant tonic – inject field horsetail or nettle stock
• Avoid drafts – in the greenhouse
• Keep the soil loose

Fight aphids on tomatoes

Of course, aphids are annoying. However, it should be remembered that if chemicals are used to combat this, the tomatoes may then be contaminated with poisons. So I would do without chemistry completely. The cigarette butt story is also out of the question for me, because these are no better. There are numerous home remedies that are guaranteed to help. However, they are often difficult to manufacture, have a strong smell or have other disadvantages. You just have to try out for yourself what you can best live with. I usually use a sharp jet of water and just wash away the pests. This is usually sufficient, if not, the action is repeated again.

It is important to regularly check the tomato plants for pest infestation. If the pests are discovered early, it is still quite easy to get a grip on them. Once they have multiplied and spread en masse, it becomes much more difficult. If aphids have been discovered, it is advisable to isolate the infected plants so that the neighbors are not also infected. Of course, this is only possible with potted plants and not with planted specimens.

Home remedies

Many means of injection are recommended. Everyone has their own secret recipe. It is important with all means not to spray or spray in the sunshine, because this can lead to burns. With soft soap solutions, it is important to use only potash soap without additives and under no circumstances normal household soap.

Cum with

• Stinging nettle manure (500 g of nettles that have not yet bloomed in a bucket with 5 liters of water. Let the mixture stand for 24 hours. Sieve out the nettles and spray the nettle extract on the tomatoes, also from below, under the leaves)
• Vinegar-water mixture (1 tablespoon vinegar to 1l water)
• Fermenting nettle broth
• Potato boiling water
• Garlic broth
• Milk-water mixture 1: 1
• Rainfarntee
• Rhubarb leaf tea
• Soft soap solution
• Vermouth tea
• Onion peel tea

Pollinate with

• Algae lime
• Rock flour
• Wood ash
• Maizena (potato starch)

Beneficial insects

Establishing beneficial insects in the garden is a good idea. They are always hungry and eat a lot of aphids. The following animals are helpful: lacewing, gall flies, black ladybirds with red spots, their larvae, earwigs, centipedes, flower bugs, predatory beetles, parasitic wasps, hoverfly larvae, harvestmen, soft beetles and birds, e.g. black redstart, warbler, titmouse, sparrow, goldfinch, leaf warbler and small woodpecker .

Predatory gall mosquitoes, parasitic wasps and predatory bugs are helpful for aphid decimation in the greenhouse. You have to watch out for the temperatures. Gall mosquitoes in particular need temperatures above 10 ° C. You can buy numerous beneficial insects in stores. You can either order them at the DIY store or garden center or have them sent to you via a mail order company.

Mechanically remove aphids

In my opinion, the best method is to spray the aphids off with water. The garden hose does a good job there. Spray on the stems with a powerful jet, it washes away the unloved companions. The jet has to be strong, but not so strong that it can damage the tomato plant. I also use this method for roses, shrubs and container plants and I am extremely satisfied with the results.

Another way to mechanically remove aphids from tomatoes is to simply wipe them off with your fingers. Disgusting people better put on gloves, everyone else does it without. In this way, the pests can be stripped off very well, especially on stems. It is also helpful to wipe off the aphids with a cotton ball soaked in alcohol or a cotton swab.

Defensive or intercepting plants

If you place such plants in the immediate vicinity of the tomato plants, these pests repel or attract them. With tomatoes, it can help to plant nasturtiums or hard-working lizards at some distance. These two plants magically attract aphids. So one has to hope that the pests will be attracted to these plants in such a way that they ignore the tomatoes. Usually this works pretty well because aphids aren’t really eager for tomatoes. Savory is also said to help when planted next to tomatoes. It repels lice.

Gelbsticker

Yellow stickers help against winged aphids. They work best in the greenhouse, of course, but they can also be used outdoors. The winged pests are attracted to the sticky board by the strong color.

Important
Where aphids appear, ants are not far either. Ants protect the pests and live on them. They eat the honeydew and breed aphids as pets. It is therefore important that something is done about the ants as well.

Funds from the trade

If it takes too long or is too complicated to create your own spray solution, you can also buy ready-made solutions.

• Naturen® BIO Pest Free Fruit & Vegetables – means based on rapeseed oil, ready to use, against sucking pests, no lasting effect, sometimes you have to repeat the process, 750 ml about 10 euros
• Bayer Garten – Pest Free NEEM – Active ingredient: Seed extract of the neem tree, for organic farming, 30 ml about 12 euros
• Natria Bio-Pest-Free Akut from Bayer – concentrate, natural active ingredients, high proportion of rapeseed oil, not dangerous to bees, do not eat tomatoes 3 days after the treatment, 250 ml about 12 euros
• Vegetable pest-free Decis AF from Bayer – pump spray, contact and food poison, active ingredient deltamethrin (very controversial), dangerous for bees, 1,000 ml about 14 to 15 euros

Conclusion
Aphids on tomato plants are a nuisance. They weaken the plants, can transmit viral diseases and allow fungal spores to colonize. It is important to recognize the pests in good time and to take countermeasures as soon as possible before the insects can multiply. Many home remedies work well, even if you have to repeat the treatment several times. These agents are absolutely preferable to chemical agents. There are also ready-made remedies available in stores. The ones with natural ingredients aren’t bad either, but they are expensive. Nettle broth or similar products are the better option, because they cost nothing or almost nothing.