Are you learning how to grow carrots and want to know what companion plants for carrots will offer the best growth assistance?
Carrots are an amazingly versatile plant for your garden and come in various shapes, colours and sizes. Sown from as early as March, carrots will be a staple food source right the way through the year and store well over winter too.
However, many insects in the garden love carrots just as much as we do, so finding the right companion plants for carrots is essential. Here we look at the 10 best companion plants you can pair up with your carrots to give them the best chance possible.
What is Companion Planting?
Companion planting is a gardening practice where different crops are planted close together to mutually benefit each other. This method improves the overall health and yield of the garden while making efficient use of space.
Benefits of Companion Planting
- Pest Control: Certain plants can naturally repel insects or attract beneficial insects that help control pests.
- Improved Health: Some companions can improve plant health by enhancing soil nutrients or providing shade and support.
- Better Yields: Complementary plants can optimize resources like light, water, and nutrients, potentially leading to higher yields.
- Disease Prevention: Spacing out plants that are susceptible to the same diseases can prevent the spread of those diseases.
- Weed Suppression: Tightly spaced companion plants can shade the soil, preventing weeds from growing.
What Shouldn’t You Plant With Carrots?

Just as important as what to plant with carrots is what not to plant with them. Fennel and dill can both produce a range of chemical compounds which can affect how carrots develop. In addition, parsnips are similar in nature to carrots, so it’s likely they’ll draw in the kind of pests which destroy carrot crops.
Cucumbers and squash will stunt the ability of carrots to grow effectively as they can compete too much for nutrients and space. Root and tuber type vegetables like potatoes too are not a good idea, as they can disturb the growing progress and steal vital nutrients.
With that being said, let’s now look at the best companion plants for carrots.
1. Onions

Onions, whether red or yellow, are ideal companion plants for carrots as they release a volatile scent that deters a wider variety of pests that can damage your growing carrots. Carrot rust flies are a significant culprit of damage in the garden but remember that onions can take a long time to mature, so get them planted before the carrots for the best results.
2. Brassicas

A broad term for dark green leafy plants such as cabbage, broccoli and kale, brassicas are excellent for planting alongside carrots by acting as a disguise with their large leaves. The carrots also work to help brassicas by potentially preventing cabbage root fly from laying their eggs close by.
3. Tomatoes

Although tomatoes grow differently to carrots, they are surprisingly good carrot companion plants for your vegetable garden. Tomatoes are known to produce solanine, a known type of insecticide. In return, carrots control caterpillars on the tomato plants by bringing the attention of parasitic wasps which feast on them. They can also provide shade to carrots on warmer days, especially if grown in a polytunnel.
4. Lettuce

The root systems of these two vegetable plants allow a symbiosis to occur because lettuces have a shallow rooting system compared to deeply extending carrot roots. The large lettuce leaves can also provide a measure of shade for the carrots.
5. Chives

Other alliums like onions, carrot flies are put off by the strong smells released by this herb, so you can be sure they don’t attack your growing roots. In addition, they won’t complete with root space as chives grow out instead of deep down as carrots do.
6. Rosemary

Pungent smells strongly deter carrot rust flies, so if you have a rosemary bush growing near your carrots, they’ll not likely pay a visit. It acts as a masking scent and a deterrent for these pesky insects.
7. Leeks

As with chives and onions, here we have one of our favourite companion plants for carrots – the leek! Carrots release a specific aroma that attracts carrot flies; however, leeks also emit odours that mask the carrot smell and deter these creatures.
8. Radishes

One of the fastest growing vegetables around, radishes and carrots have a root system which is complementary to each other. Radishes are shallow rooters, and carrots push deep down as they are root vegetables. What’s more, the small size of radishes isn’t going to compete with carrots.
9. Legumes

What legumes like beans and peas do excellently is fix nitrogen in the soil with their roots, capturing it from the air and storing it underground. Planting them close to your carrots allows them access to nitrogen to boost their growth. Peas and beans grow upwards, too, so you aren’t going to shade them.
10. Nasturtiums

An excellent all-rounder, nasturtiums are great companion plants for carrots because they naturally repel all manner of insects and attract bees and other pollinators to the garden. Aphids, beetles and whitefly are all repelled by the scent of nasturtiums planted close to carrots.
11. Daffodils

Daffodils are more than just springtime beauties; they are a natural deterrent against rodents that may target your carrot crop.
Planting daffodils around the periphery of carrot beds in a greenhouse tunnel, or raised gardens can keep away squirrels, voles, foxes, and mice, thanks to their poisonous bulbs which these animals find repulsive due to their smell and bitter taste.
However, avoid planting them directly with carrots as they can dominate the space over time.
12. Oregano

Oregano is another excellent companion for carrots.
Its potent essential oils, such as thymol and carvacrol, naturally repel garden pests like nematodes and rust flies.
Additionally, it’s believed that oregano can subtly improve the flavour of carrot roots as they mature, making them tastier when harvested.
13. Marigolds

Marigolds are not only aesthetically pleasing with their bright orange and yellow blooms, but they are also highly effective in a vegetable garden.
These flowers are particularly beneficial alongside carrots as their strong fragrance wards off pests like carrot rust flies and psyllids, which can harm young plants.
Moreover, marigolds are thought to boost the nutrient quality of carrots, increasing their carotenoid and sugar levels.
Choosing The Best Companion Plants for Carrots

So there you have it, a whole host of yummy vegetables that make the perfect companion plants for carrots. Some carrot companion plants will actively deter pests, and some will provide much-needed shade, whereas others will give it the nutrients it needs and not compete with the underground root system of these vegetables.
FAQs
What not to plant next to carrots?
Avoid planting carrots next to dill, parsnips, and potatoes as they can compete for resources or exacerbate pest issues.
What compliments carrots in the garden?
Carrots are well-complemented by tomatoes, leeks, rosemary, and sage in the garden, which can help improve growth and reduce pests.
What to plant with carrots to prevent carrot fly?
Planting onions, leeks, rosemary, and sage with carrots can help deter carrot flies due to their strong scents.
Sources
SCI. (2010) Knowing Your Alliums. [online] Available at: https://www.soci.org/chemistry-and-industry/cni-data/2010/10/knowing-your-alliums [accessed 20/09/24]
