Following my blog post of a couple of months ago on flowers to grow with vegetables http://www.my-garden-school.com/10-flowers-to-grow-with-vegetables/, I had so many valuable comments and ideas I thought I would share some with you.
There is undoubtedly great interest in natural pest control and growing plants together which benefit one another. This companion planting can mean growing a flowering plant which attracts pollinating insects, needed for fruit set.
Or it might be the rather mysterious effects of growing certain flowering plants with vegetables to improve their flavour. Some of your suggestions included ideas for companion planting to deter pests amongst the flowers, as well as on the vegetable plot.
Squirrels and tomatoes
Several readers seem to have trouble from squirrels eating their tomatoes. I was interested to hear that squirrels and birds may be eating tomatoes for the water content.
Therefore, if you provide water in the garden for them to drink it may reduce their desire to take the tomatoes.
This sounds logical but I have a horrible feeling that the squirrels just love the taste of tomatoes. Which would you rather have? Pasta with water or tomato sauce?
Marigolds, slugs and other pests
Marigolds got a lot of comment. I am assuming that most refer to the French and African marigolds which contain natural pyrethrins, rather than the pot marigold or calendula.
Some reports suggest that they deter deer, however I think you would have to have a lot of strong growing African marigolds for this to be effective.
A reader in Canada was put off them: “I was all set to buy marigolds to interplant with the veggies and herbs we are planting at my daughter’s school, but the garden helper said they just attract slugs and should be left out. I am hearing so many good things about them…do the benefits outweigh the risk of slugs?”
Young French and African marigold plants certainly can be targeted by slugs, but surely this is an advantage. You can use them as a decoy to attract the slugs and keep them away from your veggies.
Use an organic slug bait or beer trap and you catch the slugs as they head for the marigolds; the marigolds live on to deter other pests.
Another reader reported using marigolds as a boundary around the garden to keep out slugs in a damp environment? Has anyone else got experience of using them in this way?
Marigolds were also recommended to deter rabbits and mice. I was very interested in the latter because mice do keep stealing my peas.
One reader suggested that they are good at getting rid of nematodes and suggested planting them between roses every few years to keep these eelworms at bay.
You said that Nasturtium is a magnet to caterpillars. Why do you want caterpillars visiting your veg.? What do you mean by “its a good indicator plant?” This comment made me realise that I hadn’t explained myself when I referred to an ‘indicator plant’.
As the nasturtiums are so attractive to certain caterpillars they are the first to show signs of damage. As soon as you see it you can then take precautions to protect your precious vegetables. This technique can be used as part of a pest control programme.
If you have a lot of pots and containers, a heuchera in a pot is a good idea. This will nearly always be the first plant to show signs of vine weevil damage. You can then take precautions to drench it and other vulnerable subjects with a biological (or chemical) vine weevil control.
“I have found that catnip planted around my eggplants keep those tiny flea beetles from chewing up the leaves. As I have all raised beds and containers they are planted in pots so I am not sure if it is invasive or not.”
I always recommend nepeta as a perennial to grow to attract bees and butterflies, so it is interesting that this is another plant that appears to also repel certain insects.
Catnip is highly aromatic so I suppose it is the vaporising oils from the leaves and stems that can work as an insect repellent. Our cats go crazy for it; so that’s one pest it doesn’t repel.
I’ve never found it to be invasive, but plants behave differently in different regions. A treasured ornamental in one country can be an invasive pest in another. Anyone with any experience of catnip?
“Sunflowers are great, not because they deter anything in particular, but they always look happy and they provide shade for pumpkins to grow under. Also climbing beans can grow up them”.
I loved this comment. Sunflowers are very good at attracting bees, and they do provide wonderful seeds for birds in fall and winter. You can simply dry the heads and hang them up and the birds do the rest.
However I hadn’t thought about the benefit of shade, or the stems as useful supports for beans. I’m going to try this next year. If it works it could look so much more attractive than the usual frame or wigwam of canes.
Beebalm (Monarda citriodora)
“I grow lemon Beebalm under my apple tree and the sent wafting up from it keeps away the pests like caterpillars on my apples. Beebalm is a very tidy plant that grows easily but is not at all invasive.”
Lemon beebalm is a native of the US. It has highly aromatic foliage and attractive flowers. This is a really useful tip and a plant I am not familiar with.
It could be really useful planted amongst roses to deter pests; one of the most commonly asked-about problems. Fruit trees always suffer from fungal and insect pests so anything that helps is worth knowing about!
Lavender is undoubtedly very good at attracting bees and pollinators. It is a favourite food source for honey bees. One or two suggested planting it between roses to keep the deer away. I think you would have to be lucky for this to work.
I used to recommend lavender as deer proof, but have known them eat and destroy it in some gardens. I suppose it all depends on the taste of your deer.
Companion planting is such a big and fascinating subject. I will be delighted to receive any more of your suggestions and comments. There are plenty of great ideas out there!