5 Things You Should Never Grow in a Greenhouse

What Not to Grow in a Greenhouse

A greenhouse is a wonderful way to extend your growing season and grow plants that wouldn’t otherwise be able to thrive in your climate. However, not all plants are suitable for greenhouses. Some plants do better in outdoor gardens, while others can be harmful to grow in a greenhouse environment.

This article will discuss what not to grow in a greenhouse, and why. We’ll cover everything from toxic plants to plants that require too much space or sunlight. By the end of this article, you’ll have a good understanding of what plants are best suited for greenhouses, and you’ll be able to avoid making any costly mistakes.

| What Not To Grow In A Greenhouse? | Reason | Alternatives |
|—|—|—|
| Tomatoes | Tomatoes are susceptible to pests and diseases that thrive in greenhouses. | Peppers, cucumbers, eggplants, squash |
| Melons | Melons require a lot of space and airflow, which can be difficult to provide in a greenhouse. | Tomatoes, peppers, cucumbers, eggplants, squash |
| Cabbage | Cabbage is prone to pests and diseases that can spread quickly in a greenhouse. | Broccoli, cauliflower, kale, collard greens |
| Lettuce | Lettuce is sensitive to heat and humidity, which can be common in greenhouses. | Spinach, arugula, Swiss chard, kale |

1. Plants That Are Toxic to Humans or Pets

When choosing plants for your greenhouse, it is important to be aware of which plants are toxic to humans or pets. Some plants can cause mild skin irritation, while others can be fatal if ingested. It is important to take precautions to protect yourself and your pets from these plants.

Plants that produce poisonous sap or berries

• Oleander (_Nerium oleander_) is a popular ornamental shrub that is toxic to both humans and animals. All parts of the plant contain a poisonous sap that can cause vomiting, diarrhea, and cardiac arrhythmias.
• Castor bean plant (_Ricinus communis_) is another popular ornamental plant that is toxic to both humans and animals. The seeds of the castor bean plant contain a toxin called ricin, which can cause severe poisoning.
• Foxglove (_Digitalis purpurea_) is a perennial herb that is toxic to both humans and animals. The leaves, flowers, and seeds of the foxglove plant contain a toxin called digitalis, which can cause heart arrhythmias.
• Dumbcane (_Dieffenbachia sequine_) is a popular houseplant that is toxic to both humans and animals. The sap of the dumbcane plant can cause skin irritation and swelling, and ingestion can cause vomiting, diarrhea, and difficulty breathing.
• Philodendron (_Philodendron spp._) is a genus of flowering plants that is toxic to both humans and animals. The sap of philodendron plants can cause skin irritation and swelling, and ingestion can cause vomiting, diarrhea, and difficulty breathing.

Plants that are allergens

• Marigold (_Tagetes spp._) is a popular garden flower that is a common allergen. The pollen from marigolds can cause allergic reactions in people who are sensitive to them.
• Ragweed (_Ambrosia spp._) is a common weed that is a major allergen. The pollen from ragweed can cause allergic reactions in people who are sensitive to them.
• Goldenrod (_Solidago spp._) is a common weed that is a major allergen. The pollen from goldenrod can cause allergic reactions in people who are sensitive to them.
• Chrysanthemum (_Chrysanthemum spp._) is a popular garden flower that is a common allergen. The pollen from chrysanthemums can cause allergic reactions in people who are sensitive to them.
• Daisies (_Bellis perennis_) are a popular garden flower that is a common allergen. The pollen from daisies can cause allergic reactions in people who are sensitive to them.

Plants that are poisonous to animals

• Lilies (_Lilium spp._) are a popular garden flower that is poisonous to cats. Ingesting even a small amount of lily can cause kidney failure in cats.
• Tulips (_Tulipa spp._) are a popular garden flower that is poisonous to dogs. Ingesting tulip bulbs can cause vomiting, diarrhea, and abdominal pain in dogs.
• Hyacinths (_Hyacinthus orientalis_) are a popular garden flower that is poisonous to dogs. Ingesting hyacinth bulbs can cause vomiting, diarrhea, and abdominal pain in dogs.
• Daffodils (_Narcissus spp._) are a popular garden flower that is poisonous to dogs. Ingesting daffodil bulbs can cause vomiting, diarrhea, and abdominal pain in dogs.
• Iris (_Iris spp._) are a popular garden flower that is poisonous to dogs. Ingesting iris rhizomes can cause vomiting, diarrhea, and abdominal pain in dogs.

2. Plants That Are Difficult to Grow in a Greenhouse

When choosing plants for your greenhouse, it is also important to consider the growing conditions in your greenhouse. Some plants are more difficult to grow in a greenhouse than others.

Plants that require a lot of space

• Trees and large shrubs can be difficult to grow in a greenhouse because they require a lot of space.
• Vines can be difficult to grow in a greenhouse because they need to be trained to climb a support.
• Climbing roses can be difficult to grow in a greenhouse because they need to be trained to climb a support.
• Bulbs that produce large plants, such as dahlias and gladiolus, can be difficult to grow in a greenhouse because they need a lot of space to grow.
• Perennials that produce large plants, such as peonies and delphiniums, can be difficult to grow in a

3. Plants That Are Not Suitable for the Climate in Your Greenhouse

When choosing plants for your greenhouse, it is important to consider the climate in your area. If you live in a cold climate, you will need to choose plants that are cold-hardy. If you live in a hot climate, you will need to choose plants that are heat-tolerant. And if you live in a dry climate, you will need to choose plants that are drought-tolerant.

Plants that are not cold-hardy

If you live in a cold climate, you will need to choose plants that are cold-hardy. This means that they can withstand freezing temperatures without being damaged. Some examples of cold-hardy plants include:

• Roses
• Peonies
• Lilies
• Crocuses
• Daffodils
• Hyacinths
• Tulips
• Shasta daisies
• Daylilies
• Hostas
• Ferns

Plants that are not heat-tolerant

If you live in a hot climate, you will need to choose plants that are heat-tolerant. This means that they can withstand high temperatures without being damaged. Some examples of heat-tolerant plants include:

• Cacti
• Succulents
• Palms
• Hibiscus
• Bougainvillea
• Lantana
• Verbena
• Marigolds
• Zinnias
• Petunias
• Geraniums

Plants that are not drought-tolerant

If you live in a dry climate, you will need to choose plants that are drought-tolerant. This means that they can withstand long periods of drought without being damaged. Some examples of drought-tolerant plants include:

• Cacti
• Succulents
• Agave
• Yucca
• Aloe vera
• Opuntia
• Euphorbia
• Lavender
• Rosemary
• Sage
• Thyme

4. Plants That Are Pest- or Disease-Prone

In addition to considering the climate in your area, you also need to consider the pests and diseases that are common in your area. If you choose plants that are attractive to pests or susceptible to diseases, you will have a hard time keeping them healthy.

Plants that are attractive to pests

Some plants are more attractive to pests than others. This is because they produce certain scents or chemicals that pests are attracted to. Some examples of plants that are attractive to pests include:

• Roses
• Tomatoes
• Peppers
• Squash
• Cucumbers
• Melons
• Grapes
• Strawberries
• Raspberries
• Blackberries

Plants that are susceptible to diseases

Some plants are more susceptible to diseases than others. This is because they have weak immune systems or they are grown in conditions that are conducive to disease. Some examples of plants that are susceptible to diseases include:

• Tomatoes
• Peppers
• Squash
• Cucumbers
• Melons
• Grapes
• Strawberries
• Raspberries
• Blackberries

Plants that are difficult to treat for pests or diseases

Some plants are difficult to treat for pests or diseases. This is because they are either difficult to reach or they have a lot of leaves that make it difficult to see the pests or diseases. Some examples of plants that are difficult to treat for pests or diseases include:

• Roses
• Tomatoes
• Peppers
• Squash
• Cucumbers
• Melons
• Grapes
• Strawberries
• Raspberries
• Blackberries

When choosing plants for your greenhouse, it is important to consider the climate in your area, the pests and diseases that are common in your area, and the difficulty of treating pests or diseases. By choosing plants that are suitable for the climate in your area and that are not attractive to pests or susceptible to diseases, you can help to ensure that your greenhouse plants are healthy and productive.

Additional Tips for Choosing Plants for Your Greenhouse

• Choose plants that are the right size for your greenhouse.
• Choose plants that have similar light and water requirements.
• Choose plants that will bloom at different times of the year so that you have flowers all year long.
• Choose plants that are easy to care for.
• Choose plants that you enjoy looking at and smelling.

By following these tips, you can create a beautiful and productive greenhouse that will add beauty and enjoyment to your home.

What Not to Grow in a Greenhouse?

• Vegetables that are sensitive to high humidity, such as tomatoes, peppers, and eggplants. These vegetables will develop diseases and rot if they are grown in a greenhouse with high humidity.
• Fruits that need to be pollinated by insects, such as apples, pears, and peaches. The insects will not be able to reach the flowers in a greenhouse, so the fruits will not develop properly.
• Perennials that need cold winter temperatures to bloom, such as dahlias, gladiolus, and peonies. These plants will not bloom properly if they are grown in a greenhouse year-round.
• Tropical plants that need warm temperatures all year round, such as bananas, mangoes, and coconuts. These plants will not survive the cold winter temperatures in a greenhouse.
• Medicinal herbs that need full sun to develop their medicinal properties, such as ginseng, goldenseal, and echinacea. These herbs will not develop their medicinal properties if they are grown in a greenhouse with partial shade.

Tips for Growing Vegetables in a Greenhouse

• Choose vegetables that are tolerant of high humidity, such as lettuce, spinach, and carrots.
• Grow vegetables in pots or raised beds so that the roots can drain properly.
• Ventilate the greenhouse regularly to prevent the humidity from getting too high.
• Water the vegetables regularly, but do not overwater them.
• Fertilize the vegetables regularly, but do not overfertilize them.

Tips for Growing Fruits in a Greenhouse

• Choose fruits that do not need to be pollinated by insects, such as strawberries, blueberries, and raspberries.
• Grow fruits in pots or raised beds so that the roots can drain properly.
• Ventilate the greenhouse regularly to prevent the humidity from getting too high.
• Water the fruits regularly, but do not overwater them.
• Fertilize the fruits regularly, but do not overfertilize them.

Tips for Growing Perennials in a Greenhouse

• Choose perennials that are hardy in your climate and do not need to be exposed to cold winter temperatures.
• Grow perennials in pots or raised beds so that the roots can drain properly.
• Ventilate the greenhouse regularly to prevent the humidity from getting too high.
• Water the perennials regularly, but do not overwater them.
• Fertilize the perennials regularly, but do not overfertilize them.

Tips for Growing Tropical Plants in a Greenhouse

• Choose tropical plants that are hardy in your climate and can withstand the cold winter temperatures.
• Grow tropical plants in pots or raised beds so that the roots can drain properly.
• Ventilate the greenhouse regularly to prevent the humidity from getting too high.
• Water the tropical plants regularly, but do not overwater them.
• Fertilize the tropical plants regularly, but do not overfertilize them.

Tips for Growing Medicinal Herbs in a Greenhouse

• Choose medicinal herbs that are tolerant of partial shade and do not need full sun to develop their medicinal properties.
• Grow medicinal herbs in pots or raised beds so that the roots can drain properly.
• Ventilate the greenhouse regularly to prevent the humidity from getting too high.
• Water the medicinal herbs regularly, but do not overwater them.
• Fertilize the medicinal herbs regularly, but do not overfertilize them.

  there are a number of plants that should not be grown in a greenhouse. These include plants that are toxic to humans or animals, plants that require a lot of space, and plants that are not tolerant of the high humidity and warm temperatures found in greenhouses. By avoiding these plants, you can help to create a safe and healthy environment for your plants and yourself.

Here are some key takeaways from this article:

• Toxic plants should not be grown in a greenhouse, as they can pose a danger to humans and animals.
• Large plants should not be grown in a greenhouse, as they will not have enough space to grow properly.
• Plants that are not tolerant of high humidity and warm temperatures should not be grown in a greenhouse.
• By following these tips, you can help to create a safe and healthy environment for your plants and yourself.