Succession Planting: 11 Vegetables Not To Plant Together

Backyard Spruce

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You may be asking yourself, what succession vegetable plants do not mix well together or sowed into the same soil after a spring harvest?

In New England, Zone 5, we are lucky to have two cool season growing periods (spring and fall) with a warm season growing period (summer) in between. This allows New England gardeners to optimize their garden’s harvest yield by planting quick-growing vegetables to harvest in each season and planting new vegetables once a new season is starting.

The general practice is fairly simple, do not plant successive crops of the same botanical family on the same ground. Here’s an example, once you harvest a root vegetable such as carrots or radishes you should then succession plant a vegetable in which you harvest their leaves or seeds, such as lettuce or beans.

If you do grow the same vegetable or same botanical family in the same spot for two or three successive harvests, you must make extra efforts to keep the ground fertile by replenishing nutrients between plantings.

Succession Planting Vegetable Friend or Foe Guide

In Zone 5 gardening, you have many options of vegetables to choose from for your garden. But which vegetables get along with each other and which vegetables dislike each other?

New England vegetable garden with variety of different plants

While most vegetable plants in the garden can be grown just fine next to one another, there are a few that don’t mix well. Some plants compete for the same nutrients or demand a lot of space. Another consideration is that some vegetable plants will attract damaging insect pests or are more susceptible to fungi diseases that could spread over to more fragile vegetable plants.

Here are some incompatible plant combinations.

VegetableFriends (Likes)Foes (Dislikes)
BeansCarrots, Celery, Cucumbers, Potato, MarigoldsFennel, Onions
BeetsLettuce, Onions, CabbageBeans, Mustard
CarrotsBeans, Lettuce, Radish, Onions, TomatoesDill
CornBeans, Cucumber, Peas, Potato, PumpkinTomatoes
CucumbersBeans, Corn, Peas, Radishes, SunflowersPotatoes, Aromatic Herbs
LettuceBeets, Carrots, RadishesBroccoli, Brussel Sprouts, Cabbage, Kale
OnionsBeets, Carrots, Cucumbers, Lettuce, Radishes, Strawberries, TomatoesBeans, Peas
PeasBeans, Carrots, Corn, Cucumbers, Potato, Radishes, TurnipsGarlic, Leeks, Onions, Shallots
RadishesBeans, Beets, Carrots, Cucumber, SpinachBroccoli, Brussel Sprouts, Cabbage, Cauliflower, Turnips
TomatoesCarrots, Onions, ParsleyCabbage, Cauliflower, Potato
ZucchiniBeans, Dill, Garlic, PeasCorn, Cucumber, Fennel, Potato, Pumpkin, and other Squashes

Incompatible Succession Vegetable Plants

Gardening can be a rewarding pastime, but it has its challenges. One of the most common issues gardeners face is dealing with incompatible succession vegetable plants. Knowing which plants to pair with one another can make or break a successful harvest, the growing period is short and mistakes cannot be made for companion crops.

Different vegetable plants that like being next to each other

Here are a few plants that don’t play well with each other.

Beans and Onions

Beans are considered an allelopathic vegetable plant, which means they produce allelopathy in the soil that will hinder the growth of another plant nearby. This causes beans to not grow well with members of the onion family, such as onion, leek, chives, and garlic. But beans are great for keeping weeds down!

Carrots and Celery

Carrots and celery are a pair of our favorite vegetables for a veggie platter with dip, but these vegetable plants should avoid each other in the garden.

Both carrots and celery require moist soil and a shady location. It is best to separate these two vegetables in your garden with a taller leafy vegetable plant like beans or tomatoes to provide evening shade and keep the bottom soil moist in the heat of the day.

Corn and Tomatoes

Corn and tomatoes will fight each other for soil nutrients when planted next to each other. This can negatively hinder their growth and vegetable yield during harvest.

Corn and tomato also share similar risks for pests and certain types of fungus, so by planting them next to each other you are risking your entire harvest should one plant gets sick. This can be quite the upset when having to chop down both these vegetables before your harvest.

Cucumber and Herbs

The problem with cucumber is that it can take on flavors it is exposed to while growing or even in your fridge! Cucumbers are known to take on the flavors of aromatic herbs. So keep herbs like basil, cilantro, parsley, rosemary, and sage away while in your garden.

Lettuce and Broccoli

Lettuce and broccoli both require similar nutrients from the soil which will lead to them competing against each other and reducing the yield of your harvest.

Ideally, you’d want to separate these two vegetable crops with a root vegetable, such as beets, carrots, or radishes as these vegetables do not heavily rely on the same nutrients to grow and will create a barrier between the other competing plant.

Potatoes and Sunflowers

If you are growing potatoes and sunflowers in your garden, do your best to separate the two. Sunflowers, like beans, actually produce a chemical called allelopathy. This chemical will weaken the growth of potatoes causing their harvest to be smaller in size and misshapen.

However, do not be discouraged by sunflowers as their allelopathic chemical can be beneficial for your garden as it also lessens the growth of weeds!

Pumpkins and Zucchini

Pumpkins are voyaging garden plants, they like to spread and take up a lot of space. They will end up smothering and choking out any zucchini that competes for water, nutrients, and space. Pumpkins like to sprawl outward with their vines snaking up anything they can touch, this can be damaging to most other vegetable plants.

Both pumpkins and zucchinis are powerhouses when it comes to nutrient and water absorption. These vegetable plants produce massive fruits which makes them demanding for resources in the soil. It is best to separate pumpkin and zucchini plants in your garden so that they do not compete with each other.

Pumpkins and zucchinis will also cross-pollinate with each other, which can alter the vegetable’s look or size if grown again from the cross-pollinated seeds.