The 10 Best Summer Crops for a Greenhouse

Summer is in full swing, and as temperatures rise, your greenhouse becomes a hotspot for cultivating an array of heat-loving crops. Growing in a greenhouse can be incredibly rewarding, offering an extended growing season and a bountiful harvest of fresh produce. Here are some of the best summer crops to thrive in a greenhouse environment:

1. Tomatoes

Tomatoes are the quintessential summer crop. They thrive in the warmth and sunlight of a greenhouse, producing juicy, flavorful fruits. Opt for indeterminate varieties like ‘Sungold’ or ‘Brandywine’ for a continuous harvest throughout the summer. Ensure good ventilation and consistent watering to prevent issues like blossom end rot.

2. Peppers

Both sweet bell peppers and spicy chili peppers are excellent choices for a hot greenhouse. These sun-loving plants benefit from the controlled environment, producing vibrant and abundant harvests. Varieties like ‘California Wonder’ and ‘Jalapeño’ are particularly popular. Stake your plants and provide adequate airflow to keep them healthy.

3. Cucumbers

Cucumbers flourish in the warm, humid conditions of a greenhouse. Choose varieties such as ‘English Telegraph’ or ‘Marketmore’ for best results. Train them to grow vertically on trellises to maximize space and ensure good air circulation. Regular watering and feeding will keep your cucumber plants producing crisp, refreshing fruits all summer long.

4. Eggplants

Eggplants, with their striking purple fruits, are another heat-loving crop perfect for greenhouse cultivation. Varieties like ‘Black Beauty’ and ‘Little Finger’ perform well in high temperatures. Ensure they receive plenty of sunlight and consistent moisture to encourage healthy growth and abundant fruiting.

5. Basil

Basil is not only a delightful addition to your summer recipes but also a fantastic companion plant for tomatoes. It thrives in the warmth of a greenhouse, producing lush, aromatic leaves. Varieties like ‘Genovese’ and ‘Thai Basil’ are popular choices. Harvest regularly to encourage bushy growth and prevent flowering.

6. Zucchini

Zucchini is a prolific summer squash that thrives in warm conditions. Varieties like ‘Black Beauty’ and ‘Golden Zucchini’ are well-suited for greenhouse growth. These plants can produce a high yield, so be prepared for a bountiful harvest. Ensure they have ample space and support to manage their vigorous growth.

7. Melons

Melons, including cantaloupe and watermelon, love the heat and can produce sweet, juicy fruits in a hot greenhouse. Varieties such as ‘Sugar Baby’ and ‘Ambrosia’ are particularly suited to these conditions. Provide plenty of room for the vines to spread and consider using trellises to support the fruit.

8. Okra

Okra, known for its edible seed pods, is a heat-tolerant crop that can flourish in a greenhouse environment. Varieties like ‘Clemson Spineless’ and ‘Jambalaya’ are popular choices. Okra plants need full sun and regular watering. Harvest the pods when they are young and tender for the best flavor.

9. Herbs

In addition to basil, other herbs such as oregano, thyme, and rosemary thrive in a hot greenhouse. These Mediterranean herbs love the warmth and can add a fragrant, culinary touch to your greenhouse garden. Regular pruning encourages bushy growth and helps prevent them from becoming woody.

10. Beans

Beans, particularly bush beans and pole beans, are excellent for greenhouse cultivation. Varieties like ‘Blue Lake’ and ‘Kentucky Wonder’ perform well in the heat. Beans can grow quickly and produce an abundant harvest. Provide support for pole beans to climb and ensure consistent watering to keep the plants healthy.

Tips for Success

  • Ventilation: Ensure your greenhouse has adequate ventilation, including roof vents, side vents, and doors. Fans can help circulate air and reduce temperatures. Learn more about greenhouse ventilation.
  • Watering: Increase the frequency of watering to ensure plants do not suffer from heat stress. Drip irrigation systems can help maintain consistent soil moisture levels. Set up a drip irrigation system.
  • Shade: Consider using shade cloths during the hottest part of the day to protect your plants from intense sunlight and prevent leaf scorch.
  • Feeding: Summer crops are heavy feeders. Regularly apply balanced fertilizers to provide essential nutrients and support vigorous growth.
  • Mulching: Use mulch to help retain soil moisture and regulate temperature. This can be particularly beneficial during the hottest days of summer.
  • Pest Control: Monitor your plants regularly for pests. The warm, enclosed environment of a greenhouse can sometimes encourage pest infestations. Use organic methods like neem oil or introduce beneficial insects to keep pests at bay.
  • Heat-Tolerant Varieties: Choose varieties that are known to be more heat-tolerant. Some crops have been bred specifically to withstand higher temperatures and still produce well. 
    • Baker Creek Heirloom Seeds
      Baker Creek offers one of the largest selections of heirloom seeds suited for summer greenhouse gardening. Their seeds are known for their high quality and historical significance. Visit Baker Creek Heirloom Seeds
  • Pollination: Some greenhouse crops may require hand pollination if natural pollinators are not present. Use a small brush to transfer pollen between flowers, ensuring fruit set.

With the right care and attention, your hot greenhouse can become a summer paradise for these heat-loving crops. Employing the strategies mentioned above can help mitigate the effects of extreme heat and ensure your crops continue to thrive. Regular monitoring and adjustments will be necessary to maintain optimal growing conditions and achieve a successful harvest.

Happy gardening!

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