Petunias are a great garden annual flower, they come in a variety of styles and colours. More importantly for the vegetable grower, petunias repel many garden pests. By companion planting petunias you will have a great display that is relatively pest free.
companion planting petunias
The list of plants that are improved in some way by companion planting petunias is a long one. Before we get into it, let’s look at what insects petunias deter.
What Insects Are Repelled By Petunias?
Petunias have a reputation among gardeners as being the go to plant for repelling certain pests. These include:-
Asparagus Beetle
The asparagus beetle can defoliate asparagus plants which can lead to a lack of photosynthesis, but also can cause fungal infection. Adult asparagus beetles can fly and are skilled at finding asparagus patches. They over winter in sheltered places like grass or vegetation piles.
For much more information on asparagus beetles go to the RHS page by following this link.
Leafhoppers
These minute insects of the family Cicadellidae, suck plant sap from all manner of plants from grasses up to trees. They’re a very common pest in gardens worldwide, and they can spread viruses from plant to plant.
Aphids
These pests come in a range of colours with the most common being blackfly and greenfly. Although they do little damage to established plants, they can mean the death of many annual plants. They feed by sucking sap from plants, and they travel from plant to plant, spreading infection as they go.
Aphids are often farmed by ants for the sweet, sticky honeydew that is the waste product of the aphid, and food to the ant. For more on how to get rid of aphids naturally follow this link.
Above are the 3 main pests that will be deterred by companion planting petunias. There are many other general pests that you will notice the absence of (or not) when growing petunias.
companion planting petunias (Or What Grows Well With Petunias)
As I said at the beginning there are many plants that will benefit from companion planting petunias. Here are some of the main plants to grow with petunias.
Petunias and Tomatoes
Tomatoes are often subjected to attack by aphids, growing petunias with your tomatoes will reduce the chance of infestation. Plus petunias will attract many beneficial pollinators to your garden. If you are anywhere but the UK, you probably know all about tomato worms.
Petunias deter these pests too.
Petunias and Cucumbers
By keeping aphid attacks and leaf hopper damage down to a minimum, you will benefit from healthier cucumber plants. Petunias also attract pollinators to help pollinate your cucumbers. Which means a heavier yield. For more on companion planting cucumbers click here.
Arugula(rocket) and Petunias
Leafhoppers and aphids can decimate arugula plants, and petunias will keep them away. They also make a good display when grown together. To find out more about companion planting arugula click here.
Chillis and Petunias
Petunias will keep the pests away from your chillis, and attract pollinators. Giving you healthier plants with higher yields.
Petunias and Potatoes
Main crop potatoes are in the ground for many months, and planting petunias amongst them is beneficial. Plus it gives a colourful display to an otherwise bland area. The main reason for companion planting petunias with potatoes is the Colorado beetle.
Also known as the potato bug for obvious reasons, the Colorado beetle does serious damage to potato crops. Petunias are somewhat successful in deterring potato bugs.
Peppers and Petunias
Bees, hoverflies, and many other pollinators are all attracted to petunias. These beneficial insects will also pollinate your pepper plants. So deterring pests and increasing crops, what’s not to like?
For more on companion planting peppers go to this page.
Brassicas and Petunias
All members of the brassica family including, cabbages, broccoli, kale, Brussels sprouts, and so on… Are subject to decimation by one particular pest. The caterpillar of the cabbage white butterfly. Petunias can be used as a trap crop, to protect your brassicas.
Petunias and Grapevines
Grapes attract many pests, including moths, spider mites, and aphids. By companion planting with petunias, you will greatly reduce the chances of pests attacking your grapes. For more on companion planting grapes click here.
Petunias and Asparagus
Asparagus beetles will be less likely to attack your asparagus plants if you grow petunias as companion plants. Grow some tomatoes as well and you can pretty much guarantee beetle free asparagus. for more information on companion planting asparagus follow this link.
Sweetcorn and Petunias
The same pest that attacks tomatoes, the tomato worm, is also responsible for attacking sweetcorn. The corn earworm is the caterpillar of a particular type of moth. This caterpillar attacks tomatoes, corn, beans, tobacco, and cotton.
Thankfully not a problem in the UK, but it can be quite a serious threat to US growers. Petunias are a well known deterrent to these pests. For more information on the corn earworm follow this link to the Purdue University page.
Petunias and Beans
If you grow beans in Mexico, or in the Midwestern United States, you may know about Mexican bean beetles. They are one of the only destructive members of the ladybird(bug) family. Damage is mainly to Soybeans and can be quite severe.
Petunia companion planting will help to reduce this problem. Here’s a link to Purdue University for more information on the Mexican bean beetle. If you have a particular interest in pests that attack peas and beans follow this link to the North Carolina State University page.
For more about companion planting beans click here.
Petunias and Peas
Not only does this combination look great, it is also an effective pest deterrent. I have seen pea plants looking dead and dried out as a result of aphid damage. Growing petunias as companion plants will greatly reduce aphid numbers.
To find out more about companion planting peas follow this link.
Companion Planting Petunias Video Summary
What Not To Grow With Petunias
This is a very short list, mainly because petunias are quite companionable plants. Petunias do best in full sun or part shade, and need moderate amounts of water. So it’s best not to grow them with shade loving plants, and plants that prefer arid conditions.
So that rules out cacti, but most other plants should be great with petunias. There’s one more way petunias can help in the fight against pests.
Petunia Insect Repellent Spray
Simply place petunia leaves in a bucket of water, leave to stew for 7 days. Then strain into a spray bottle 3/4 filled with water. Add 1 teaspoon of vegetable oil, and a squirt of washing up liquid.
Spray on plants to prevent insect infestation, or as a preventative measure. Respray after rain or heavy watering.