Taming the Heat: 3 simple steps

1. Circulate the Air

Cool and Clear the Greenhouse Air. Monitor your greenhouse temperature, so you can adjust the environment as necessary. There are both natural and mechanical ways to provide your plants with the air temperatures they find comfortable in the summer greenhouse; many growers prefer a combination of the two.

For natural means, you can open doors, windows, and vents to cross-ventilate; installing base vents at the bottom of one end of the greenhouse and a louver at the opposite side of the greenhouse will promote a natural ground-up cross circulation through the greenhouse.

If natural circulation is not adequate, stale air can be pushed out with exhaust fans. The air can be kept evenly warm with circulation fans.

Louvers can also provide just the right amount of natural air into the greenhouse, with or without an associated fan. Try one of our heat sensitive louvers, which will automatically open and close based on the interior temperature.

We have plenty of other cooling and ventilation options, to suit all needs and budgets. Just click here for more.

Clear the Clutter. Circulating the air will be most effective in an uncluttered greenhouse. Move some of your plants onto benches and tables. Prune your more exuberant plants back to make sure they’re not touching one another, and move some plants outdoors if they can tolerate the heat.

2. Diffuse the Light

Indirect light is better for your plants than direct sunlight during the intensely bright and hot summer months. It penetrates from all angles, reaching deeper into the plant canopy for better growth. Also, it spreads evenly; there are no “hot spots” which can lead to plant stress and slowed growth. This gentler light also helps keep the heat down.

Shade cloth is an excellent means of reducing light and heat, and so is our patented Solexx covering. Solexx has the dual benefit of providing diffused light and cooling advantages during the hot, bright summer and heat retention during the cold weather.

3. Keep Plants Hydrated.

Summer heat can lead to excessive dryness in the air. There are several ways to keep plants properly watered.

Hand watering may work better for tender plants, but will require some time. Overhead misting may be a better option. If you’re growing tropicals that require foliar hydration, the air itself needs to be exceptionally moist.   Automatic watering systems also are very convenient, particularly for vacation time, when you’ll need something that can be easily programmed.

Damping down the greenhouse floor can also help in humid areas, because the water will evaporate during the day, humidifying the air.

Keeping your summer garden refreshed

Mulch: Spreading a 2-inch-deep layer of mulch over your soil is one of the best things you can do for your garden. The mulch blankets the ground, shielding the soil from the sun. This keeps it cooler, so your plant roots are happier, and prevents moisture loss from evaporation. There are so many organic options of mulch. Shredded wood, pine straw, a mix of grass clippings and shredded leaves, or any other organic matter is going to help your soil in the long run as it decomposes and adds to your soil structure.

Weeds: Many pesky weeds love summer heat and quickly take the jump from tiny to gigantic. It’s important to pull them from your garden, because weeds steal moisture and nutrients from your plants. Many weeds also encourage insect pests and diseases to pop up in your garden. Weeds are easiest to pull when they’re young and small. They also come out of the ground easiest when the soil is moist. Another reason to get them while they’re young: you can stop weeds from producing seeds. A single dandelion plant can produce 2,000 seeds in a year. A weed such as lamb’s quarters can produce 150,000 seeds in a year. Remove spent blooms from many of your annuals and perennials, and you might see more flowers! This process, called deadheading, prevents plants from producing seeds so they put more energy into beautiful blooms.  Deadheading cuts back on future efforts, too, for plants that self-seed. Perennials and annuals can self-seed to the point of producing too many weeds in the garden.

Watch for Pests: Like weeding, keeping an eye on pests and diseases in your yard should be done all year. But midsummer seems to be particularly popular for these gardening obstacles.  Some of the more common midsummer problems to watch for include:

  • Black spot
  • Cucumber beetles
  • Grasshoppers
  • Japanese beetles
  • Powdery mildew
  • Rust
  • Squash bugs
  • Tomato horn worms

Water:  If you experience dry summers, or a dry weather pattern, you may wish to water your garden to keep it looking its best.  Most common garden plants prefer an average of 1 inch of water a week. It’s best to apply that inch all at once to encourage plant roots to sink down more deeply in the soil.  When watering, apply water directly to the ground rather than getting a plant’s foliage wet; water sitting on the leaves can lead to disease. Soaker hoses are great for this!

Add Color with Summer Annuals:  Once summer heat arrives, many spring-blooming annuals such as pansy, viola, and osteospermum fade. Make your yard look its best by pulling out the spent plants and replacing them with heat-loving varieties such as angelonia, lantana, ageratum, coleus, pentas, portulaca, salvia, sweet potatoloving annuals grow quickly in warm temperatures and will soon provide a beautiful burst of color

Some more summer bulbs include calla, canna, and dahlia which are surefire ways to add color and drama to your landscape all summer long. These varieties are tender, so if you live in a Zone where they’re not hardy, plant them after all danger of frost has passed. Once temperatures rise, they grow quickly.

Pinch Mums and Other Late Perennials:Keep mums, sedums, asters, and other fall-blooming perennials standing tall by pinching the top inch or two of new growth. You can do so up to the Fourth of July.  Pinching the tops of the plant typically gives you a more compact, sturdy specimen. It may also give you more blooms from the sideshoots that develop, though the blooms are typically a little smaller and appear a couple of weeks later.  Other perennials that you can pinch in May and June:

  • Balloon flower
  • Bee balm
  • Goldenrod
  • Joe Pye weed
  • Perennial sunflower
  • Phlox
  • Russian sage
  • Remove Faded Flowers

Raise Your Mower:  Raise the height of your lawn-mower blade if you have cool-season grasses such as Kentucky bluegrass, rye grass, or fescues. More leaf surface keeps the plants healthier during hot, dry weather.

Start a Fall Vegetable Garden:  Vegetables fall into two basic categories: Cool-season and warm-season. The warm-season varieties — tomatoes, eggplants, peppers, cucumbers, summer squash — are all going now. Once temperatures cool, these plants will fade.  Enjoy continued harvests by planting cool-loving vegetable seeds, such as broccoli, carrots, kohlrabi, lettuce, and spinach, now so you can enjoy fresh, delicious harvests this Autumn.

June Gardening tips

Seasonal opportunities: When you can set out your tomato plants, remove the lower leaves and bury in a trench, leaving the top tuft of leaves showing. This gives the plant additional roots and strength. Remember that planting seeds in cold soil can promote disease and slow germination. Plant new starts inside a black plastic pot that has the bottom cut out and is half buried in soil to protect the plant from cutworms and to warm the soil. Everything grows very fast as the weather warms, so keep your garden weeded to give your crop optimum water and nutrients. Stressed or sickly plants invite pests and diseases. Seed fast-maturing crops every two weeks for a continual harvest. This is also an excellent time to take cuttings for the greenhouse. Root cuttings in coconut coir on your heating mat.

Aesthetic herb thymes: Give yourself a special treat this summer by adding the beauty, color and flavor of flowers to your summer salads, ice cubes and cool drinks. Some flowers to have growing in your garden include: borage (cucumber flavor), nasturtiums (sweet and spicy), chive blossoms (sweet, subtle onion flavor), calendula (saffron color), rose petals (fragrant, calming) and common orange daylily (fresh green been flavor). Also try honeysuckle, daisies, pansies, carnations, cornflowers, gladioli and geraniums. Pick fresh each day, rinse quickly under cold water and remove pistils, stamens and white base before adding to your finished dish. Young violet leaves can also be used, they contain three times the vitamin A of spinach and five times the vitamin C of orange juice!

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