The long, warm days of summer are a gift to any gardener, but for those with a greenhouse, it’s a season of incredible potential. Your greenhouse acts as a powerful engine for growth, allowing you to cultivate a wider variety of plants and extend your harvest far beyond what’s possible in the open garden. However, the intense summer sun can also create challenges like scorching heat and pest pressure. Navigating these conditions successfully is the key to a thriving summer garden under glass. This article will guide you through the essentials of What to Grow in a Greenhouse in Summer: Basic Info & Essential Tips to ensure your efforts are rewarded with a healthy, productive harvest.
Knowing what to grow in a greenhouse in summer is more than just picking your favorite vegetables; it’s about choosing plants that will thrive in the unique microclimate you’re creating. While your outdoor garden might be perfect for root crops and cabbages, your greenhouse is the ideal sanctuary for heat-loving, sun-seeking plants that would otherwise struggle in your local climate. With a little planning and the right techniques, you can create a lush, productive oasis.
What to Grow in a Greenhouse in Summer: Basic Info & Essential Tips
Your summer greenhouse is the perfect environment for plants that crave warmth and a long growing season. The controlled conditions protect them from unexpected cold snaps, heavy rain, and strong winds, giving them a consistent and ideal space to flourish.
Top Crops for Your Summer Greenhouse
Focus on plants that not only tolerate heat but truly love it. These are the stars of the summer greenhouse stage.
Tomatoes: The quintessential greenhouse crop. They will ripen faster and produce a more reliable, blemish-free crop than their outdoor counterparts. Consider growing a mix of cherry, beefsteak, and heirloom varieties for a continuous harvest.
Cucumbers: These vigorous vines adore the warmth and humidity. Provide them with a sturdy trellis to climb, and you’ll be rewarded with a prolific supply of crisp, sweet cucumbers.
Peppers and Chilies: From sweet bell peppers to fiery habaneros, all peppers thrive with the consistent heat of a summer greenhouse. The extended season allows them to fully mature and develop their complex flavors.
Eggplant: Another sun-worshipper, eggplant will produce larger and more abundant fruit in the protected, warm environment of a greenhouse.
Beans: Both pole beans and bush beans grow quickly and productively in summer greenhouse conditions. They also help fix nitrogen in the soil, benefiting other plants.
Heat-Loving Herbs: Basil, oregano, and rosemary will grow more lush and aromatic in your greenhouse than anywhere else in your garden.
Mastering the Summer Greenhouse Environment
The biggest challenge in a summer greenhouse is preventing it from becoming an oven. Effective temperature and humidity control are non-negotiable.
Ventilation is Vital: Open all vents and doors on warm days to create a cross-breeze. For even better results, consider installing an automatic vent opener, which uses a heat-sensitive piston to open vents without any electricity.
Provide Some Shade: On the hottest, sunniest days, direct sunlight can scorch leaves and overheat plants. Apply a shade cloth to the outside of your greenhouse, or use a washable shade paint. This simple step can lower the internal temperature significantly.
Damp Down the Floor:
This traditional technique involves watering the gravel or concrete floor of your greenhouse in the morning. As the water evaporates during the day, it increases humidity, which can cool the air and deter certain pests like red spider mites.
Watering Wisely: Plants in a greenhouse can dry out very quickly. Water deeply in the early morning so plants are hydrated before the heat of the day, and to allow foliage to dry, which helps prevent fungal diseases. Drip irrigation or soaker hoses are excellent for delivering water directly to the roots efficiently.
Keeping Pests and Diseases at Bay
The warm, sheltered conditions that your plants love are also attractive to pests like whitefly, aphids, and spider mites. Regular monitoring is your first line of defense.
Check the undersides of leaves every few days. Introduce beneficial insects, such as ladybugs for aphids or parasitic wasps for whitefly, as a natural form of control. Good air circulation and avoiding overcrowding your plants will also help prevent the spread of fungal diseases like powdery mildew.
Planning for a Continuous Harvest
To make the most of your space, practice succession planting. As you harvest one crop, like an early planting of lettuce, have another seedling ready to go in its place. You can also start seeds for fall brassicas, like kale and broccoli, in the shelter of your greenhouse during mid-to-late summer, giving them a strong head start before transplanting them outside.
Your summer greenhouse is a dynamic and rewarding space. By selecting the right heat-loving crops and carefully managing the temperature, humidity, and pest pressure, you can create a flourishing garden that provides fresh, homegrown produce all season long. Embrace the warmth, tend to your plants with care, and enjoy the abundant rewards of your efforts.