Gardeners do all they can to keep their plants happy and healthy, but sometimes, no matter what you do, certain plants just don't go together. Plants that don't like each other may be responding to different environmental needs, could be in direct competition with one another for major resources or one may attract insects that severely harm the other. Determining plant incompatibility can be a guess and check situation since soil types also have an influence on what plants should not be planted together.
Incompatible Garden Plants
There are a few basic rules of thumb when it comes to plants to avoid near one another. First, check that your garden plants are all about the same size and have the same light requirements. Planting very tall plants like tomato next to bush beans, for example, is a very bad idea since the tomatoes will very likely shade out the beans.
When planting taller and shorter plants together, make sure that the shorter plants are spaced far enough away and oriented so the sun will shine on them during the day. Many gardeners solve this problem by putting the shortest plants in their own row on the edge of the garden, or plant them as a border planting.
Plants that need a lot of water will cause those water haters nearby a great deal of discomfort; the same goes for fertilizer. It's always a good idea to plant things with similar nutritional and water needs together, unless they're fiercely competitive. Even then, you can often compensate by spacing them extra wide and providing enough fertilizer and water for both types of plants.
Last but not least are the plants that are allelopathic. Allelopathic plants have the capability to chemically impede the vital systems of competing plants. These plants are usually weeds, but many landscape and crop plants have been observed leaving behind allelopathic chemicals. Plant scientists are using these observations to develop better methods of weed control for farms and gardens alike.
What Plants Should Not Be Planted Together?
Many plants are believed to have allelopathic behaviors, but many remain in the realm of garden lore and lack substantial scientific documentation. Research in this area is sparse, but the list of plants believed to have allelopathic properties include:
Black walnuts have long been known to interfere with garden plants like tomatoes, eggplants, and corn. When planting broccoli in your garden, make sure that you practice good crop rotation since broccoli can leave behind residue that other cruciferous crops can't tolerate.
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Some plants, like alfalfa, seem to exhibit a remarkable type of allelopathy that interferes with the germination of their own seeds. Garlic and onions are believed to interfere with the growth of beans and peas, but seem to be compatible with most other garden denizens. Other commonly believed plant incompatibilities include the following plants to avoid near one another:
FAQs
Plants that have negative or detrimental relationships, should be planted at least two to three rows apart. Infestation of pests or disease can occur more quickly if you plant all the same crop close together.
How far apart should incompatible plants be planted? ›
Plants that have negative or detrimental relationships, should be planted at least two to three rows apart. Infestation of pests or disease can occur more quickly if you plant all the same crop close together.
What not to plant next to peppers? ›
Brassicas: Almanacs and home gardeners recommend avoiding planting brassicas (cabbage, broccoli, kale, collards, cauliflower) near peppers because they require different soil acidity levels and can deter pepper plant growth.
What should you not plant next to tomatoes? ›
10 Plants You Should Never Grow Next to Your Tomatoes
- 01 of 10. Fennel. Fennel is not a good companion for any garden crop. ...
- 02 of 10. Cabbage. Getty Images. ...
- 03 of 10. Pole Beans. Neyya / Getty Images. ...
- 04 of 10. Dill. Oxana Medvedeva / Getty Images. ...
- 05 of 10. Corn. ...
- 06 of 10. Okra. ...
- 07 of 10. Potatoes. ...
- 08 of 10. Broccoli.
Antagonistic plants for cucumbers
- Plants in the same family as zucchinis, melons and pumpkins should not be planted directly next to cucumbers.
- The same applies to Jerusalem artichokes, lovage, sage, radishes, radishes and tomatoes.
As a general rule, put tall veggies toward the back of the bed, mid-sized ones in the middle, and smaller plants in the front or as a border. Consider adding pollinator plants to attract beneficial insects that can not only help you get a better harvest, but will also prey on garden pests.
Can you grow peppers and tomatoes together? ›
Tomatoes. Although it's usually recommended to not plant tomatoes and peppers right after each other in the same bed every year, they can be grown together in the same garden bed (and then rotated to another bed next season).
What flowers not to plant with vegetables? ›
Oleander and Foxglove, while beautiful, shouldn't be planted near your vegetables. All parts of these plants are toxic and harmful to your health. Gladiolus should be kept out of the garden especially if you're growing legumes like peas and beans.
What not to plant next to zucchini? ›
Potatoes can also spread diseases such as late blight, which can also affect zucchinis. Cucumbers and pumpkins should not be planted next to zucchinis as they belong to the same family (Cucurbitaceae) and therefore attract similar pests and diseases.
What do peppers like to be planted next to? ›
If you want to grow other vegetables together with peppers, then carrots (Daucus carota subsp. sativus) or onions (Allium cepa) are good choices. Lettuces, especially varieties that grow well in semi-shade, are also great companion plants for peppers.
Zucchini can offer some shade and ground cover for peppers and the two crops grow well together. Peppers do not add any specific benefit for zucchini, but you can grow both together and have a good crop of both.
What are three mistakes to avoid when gardening with raised beds? ›
Seven Beginner Raised Bed Gardening Mistakes to Avoid
- Picking The Wrong Spot. It is a common gardening mistake made by many gardeners. ...
- Not Thinking About The Water Source. ...
- Raised Beds Placed Too Close Together. ...
- Crowding your Plants. ...
- Planting the Wrong Plants. ...
- Skipping Mulch. ...
- Not Using the Correct Soil.
Raised beds work best when you fill them with plants that need the same amount of water to grow. If you try pairing a thirsty tomato with a dry soil-loving agave, for example, one of them will suffer. Moisture-loving plants that do well in raised garden beds include cardinal flowers, sedges, and monkshood.
Should I put rocks in the bottom of my raised garden bed? ›
Contrary to popular belief, rocks do not significantly enhance drainage when put at the bottom of a raised garden bed. Eventually, the soil will fill the spaces between the rocks and actually slow down drainage.
What vegetables to keep away from each other? ›
- Keep Onions Away From Apples and Potatoes.
- Store Melons Solo.
- Keep Cauliflower Away From Apples, Kiwis, and Onions.
- Place Mushrooms Away From Pungent Foods.
- Use Your Crisper Drawer.
- Separate Ethylene Producers and Ethylene Sensitive Produce.
Which Vegetables Grow Well Together?
| Vegetable | Companion Plant | Don't Plant Together |
|---|
| Peas | Beans, carrots, corn, cucumbers, radish, turnip | Garlic, onions |
| Potatoes | Beans, corn, peas | Tomatoes |
| Squash | Corn, melons, pumpkins | None |
| Tomatoes | Carrots, celery, cucumbers, onions, peppers | Corn, potatoes, kohlrabi |
11 more rowsJun 26, 2021
The Bottom Line
“The easiest rule to follow is to just store like produce together,” Grant-Vose says. “Berries can be stored together, brassica vegetables can be stored together, leafy greens can be together, and most root vegetables (except potatoes) can go together.”
Can tomatoes and peppers be planted together? ›
Tomatoes. Although it's usually recommended to not plant tomatoes and peppers right after each other in the same bed every year, they can be grown together in the same garden bed (and then rotated to another bed next season).
