Not all plants are good neighbors in the garden. While companion planting is popular, some plant combinations can do more harm than good. They compete for nutrients, attract the same pests, or even release chemicals that harm nearby plants.
Planting incompatible crops together can stunt growth and reduce yields. This article will help you identify plants that should be kept apart. Avoiding these combinations can lead to a healthier, more productive garden.
Tomatoes and Potatoes
As both belong to the nightshade family, tomatoes and potatoes are poor companions. They attract the same pests, which can devastate both crops simultaneously. Their similar nutrient needs also mean they’ll compete for vital resources like nitrogen and potassium, weakening both plants. Plant these two separately for a healthier, more productive garden to protect your harvest from potential harm.
Carrots and Dill
Although dill and carrots belong to the same plant family, planting them together is not recommended. Dill can stunt the growth of nearby carrots, as it releases compounds that negatively affect carrot development. These two plants can also cross-pollinate, which may lead to undesirable changes in flavor and growth patterns. Keeping dill at a distance is best to ensure healthy carrot plants.
Cabbage Family and Strawberries
Strawberries and cabbage family members, like cauliflower, broccoli, and kale, make poor companions. These plants have different soil preferences, with cabbages thriving in heavier soils and strawberries favoring sandy ones. This disparity, combined with differing nutrient needs, can make strawberries more vulnerable to diseases. In Midwestern states, the shared attraction of cabbage white butterflies to both crops can lead to infestations early in the season, particularly during warm springs. Using row covers on strawberries can help minimize pest damage if grown near cabbage family crops.
Corn and Tomatoes
Corn and tomatoes are not ideal companions, as both attract the cotton bollworm, a common pest that damages them. They also share a susceptibility to fungal infections, which can quickly spread between them. To reduce pest and disease risks, it’s best to plant corn and tomatoes in separate areas of your garden.
Onions and Beans
Onions and beans should not be planted together, as onions can stunt the growth of beans. Beans also add nitrogen to the soil, harming the onions since they don’t thrive in overly nitrogen-rich soil. While beans can help deter onion flies, it’s best to plant them farther apart in the same bed for optimal results.
Fennel and Almost Everything
Fennel’s strong aroma and flavor make it difficult to pair with most plants. While some suggest growing dill alongside fennel, even that pairing can be problematic due to potential cross-pollination between the two herbs. It’s best to plant fennel in isolation to avoid garden conflicts.
Peppers and Beans
Due to their differing nutrient needs, peppers and beans don’t make ideal companions. Beans are heavy feeders that fix nitrogen in the soil by converting atmospheric nitrogen into a usable form, benefiting nearby plants. However, peppers, which do not have this ability, can struggle to absorb the excess nitrogen, leading to poor growth. Planting beans and peppers separately ensures both crops get the proper nutrients they need for healthy growth and development.
Lettuce and Brassicas
Brassicas like cabbage, broccoli, kale, and kohlrabi often compete with lettuce for the same nutrients, especially nitrogen. This competition can stunt lettuce growth and reduce its yield. Additionally, plants like broccoli and mustard greens release chemicals that can inhibit the growth of nearby leafy greens. In colder climates, such as Montana, the competition for limited sunlight during early spring can result in stunted lettuce growth when planted near tall brassicas like broccoli. Keep brassicas and lettuce separate in your garden to ensure healthy growth.
Sunflowers and Potatoes
Potatoes grow pretty quickly, and their expansive roots can interfere with other plants, including sunflowers. Potatoes are also susceptible to blight, a disease that can spread quickly to sunflowers. This combination can weaken both crops and reduce your overall harvest.
Zucchini and Cucumbers
Avoid planting zucchini alongside cucumbers, as both are vining crops that can quickly become tangled. Their sprawling vines may compete for space, overshadowing each other and stunting growth. In some cases, one plant may even choke out the other, leading to poor yields.
Radishes and Brassicas
Radishes and brassicas like broccoli, cauliflower, and cabbage should be kept apart. Radishes attract flea beetles, which are notorious for damaging brassica leaves. Additionally, brassicas release compounds that can hinder radishes’ growth, making it harder for them to thrive. For the best results, give each crop space to grow and flourish without interfering with the other.
Garlic and Asparagus
Garlic and asparagus have differing nutrient requirements, making them incompatible companions. Planting them together leads to competition for nutrients and root space, stunting asparagus growth. Asparagus, being a long-term crop, suffers from the interference of garlic’s strong root systems, hindering the healthy development of its stalks.
Beets and Climbing Beans
Beets and climbing beans don’t make great neighbors. Climbing beans tend to overshadow beets, competing for sunlight and hindering their growth. Beets also prefer slightly acidic soil, while beans thrive in neutral to slightly alkaline conditions, which creates further incompatibility. For the best results, plant bush beans with beets instead, as they offer better compatibility and allow both plants to flourish.
Celery and Corn
Celery and corn are not ideal neighbors due to corn’s high nutrient demand. Corn’s aggressive feeding habits can deplete the soil of the nutrients celery needs to thrive. Additionally, the tall corn stalks can overshadow celery, blocking the sunlight it requires for healthy growth.
Lavender and Melons
Lavender should not be planted near melons due to their conflicting water needs. Melons require frequent watering, creating a humid environment that lavender struggles with. Additionally, lavender thrives in slightly alkaline soil, while melons prefer slightly acidic conditions. These differences make them poor companions.