Ventilation/Air Circulation —
Continue to keep the greenhouse under 90 degrees F in the warmest part of the day, and the temperature as even as possible during the rest of the day.
For smaller greenhouses (up to 10’ x 12’)
I recommend installing automatic solar vent openers on the roof vents to release excess hot air. For larger greenhouses, install a worry-free automatic ventilation system.
Early in the day, open your screened door vent if you have one, and any lower fresh air vents to allow cool air to flow in. Close them in the evening to help keep the temperature more even.
Keep your air circulation fan running 24 hours a day to prevent disease, increase carbon dioxide, and ensure healthier, happy plants.
If your air circulation fan is doing a minimal job and not reaching everywhere it should, consider replacing it with a larger fan or adding another portable air circulation fan at the opposite end of your greenhouse.
Shading —
If you haven’t already done so, Shade Fabric is generally necessary by now on the roof and at least the upper half of your southern wall. Apply it on the outside of your glazing to cut the heat before it enters the greenhouse, helping to keep it cooler.
Still experiencing overheating challenges? Visit Cooling the Summer Greenhouse or give our greenhouse consultants a call 1-800-322-4707.
Watering / Humidity —
Continue daily watering. capillary matting and Self Watering Systems are handy aids, particularly at this time of year.
If you have a very large plant collection, an automatic mist system saves you much time and labor. If you live in an extremely hot climate, an Evaporative Cooling System is very effective this time of year.
Pest And Disease Control —
As plant growth continues to increase at a more rapid pace, so does the possibility of pests and disease. Watch daily for signs – especially under leaves. A Lighted Magnifier is most helpful to detect tiny unwanted guests. Check out Charley’s arsenal of effective but safe Pest Controls for fast help! See Charley’s Greenhouse Organic Pest and Disease Control Guide for images and descriptions of common unwanted insects and diseases.
More Growing Ideas —
Take advantage of starting new plants this month while the weather is warm and propagation is faster.
- Start Cape Primrose (Streptocarpus) and others for flowering later indoors.
- Sow seeds of cool-season plants for outdoor fall gardens.
- Pot up fall flowering bulbs.
- Propagate leaf cuttings of African Violet, Rex Begonia, Bougainvillea, Oleander and others.
- Propagate a wide variety of softwood cuttings like lavender, fuchsia.
Other ways to use your greenhouse during summer months —
- Transfer houseplants to the greenhouse for rejuvenation.
- Make a comfortable leisure sitting area among your favorite plants to relax and entertain in.
- Dehydrate fruit and veggies.
- Dry bulbs to replant next fall.
- Make a mini pond with fish, frogs, etc.
alias Mrs. Charley
