Why Fennel and Nightshades Should Never Be Planted Together

Why Fennel and Nightshades Should Never Be Planted Together

We love discussing how combining different plants in your greenhouse can be a great idea! Companion planting is fantastic, but it's important to do it correctly to get the best results.

Just like some people don't get along, some plants don't either! Fennel and nightshades are like bad neighbors and can harm each other if planted too close.

Imagine doing all the necessary watering and fertilizing, only to have poor germination and stifled plant growth in your greenhouse nursery and vegetable greenhouse. This can be confusing and disheartening.

Nightshades include plants like peppers, tomatoes, and eggplants. When grown alone or with good companion plants, they thrive and produce excellent harvests but do not grow them beside fennel plants. Nightshade plants have high alkaloid content, making them naturally repellant to some pests, but it’s harmful to some plants, fennel, for example.

This toxic relationship is a two-way street. Fennel plants may seem harmless on the surface, but the allelopathic compounds found in fennel have growth-inhibiting effects on some plants.

This herb will make your nightshades struggle to germinate, grow and produce fruit. The fruits produced will be lesser and more minor than the plants could have made if not planted close to fennel.

Another reason you should think twice before mixing these greenhouse plants is their nutrient and soil requirements. To grow a bountiful tomato, eggplant, and pepper harvest, your soil must be slightly acidic with a pH of 6.0 to 6.8.

On the other hand, excellent fennel production will be from alkaline soil with a pH of 7.0 to 8.0. Fennel should get fertilizer with NPK 20-5-5, while nightshades will grow with NPK averages of 5-10-10.

Since the growing requirements differ, you must place them in different beds or the fennel in your herb greenhouse. Improper fertilization can cause stunted growth for both plants.

Proper spacing is the final factor to consider when planting these two crops. Fennels will grow well when grown well in clusters and have lots of sunlight. Nightshades require more space to thrive. If planted close to fennels, they will tower over them, blocking the sunlight and affecting their growth.

So, before planting in your greenhouse, remember that not all plants get along. Even though companion planting can be a great idea, it's essential to do it correctly to get the best results. Fennel and nightshades are like bad neighbors that can harm each other if planted too close. Due to this toxic relationship, don't be disheartened when your plants don't grow as well as you expected. It's essential to consider the nutrient and soil requirements and proper spacing when planting them. So, keep these tips in mind, and happy gardening!

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