The sun is shining, temperatures are on the rise, and our gardens are flourishing. For many gardeners, our greenhouses have played an important role in the late winter and early spring. They have helped us nurture tender seedlings, get our crops started early, and look after young plants before the UK weather was truly ready for them.
But now that the scorching sun is here, we need to adjust how we are using our greenhouses, and the measures we’re taking to make sure the plants that are still in them thrive.
Here are our top five “Do”s and bottom five “Don’t”s for greenhouse gardening this summer.
TOP TIP “DO”s OF GREENHOUSE GARDENING THIS SUMMER
DO Ventilate Effectively
Make sure that air flows well through your greenhouse, by opening roof vents, side vents and doors. This is most beneficial early in the day, before the heat really sets in. If you can get a through-breeze going, all the better.
Especially if you’re going away or are prevented in any way from getting to the greenhouse to ventilate, we recommend considering automated vent openers. These nifty devices won’t break the bank, because while they’re automated, they work with some clever physics, rather than electronically. Our Rhino Greenhouses come with these as standard, however there are options that can be fitted to any greenhouse to improve air circulation in the hotter months.
DO Use the Right Amount of Shade
Airflow alone may not be enough to keep the temperature in your greenhouse from soaring. It’s time to get some shade in place, to stop your plants from scorching.
Blocking out all the light will cause issues for plant growth, so there is a balance to strike between limiting how much sunlight enters to heat the greenhouse, and still letting enough light in to support plant growth.
In general, shading 30-60% of the light in your greenhouse will do the trick. 30% for sun-hungry growers, like tomatoes, and closer to 50% for more delicate plants.
Shade can be achieved through internal or external greenhouse blinds, shade netting or shading paints. Remember to remove the shade as September arrives, as the sun lowers in the sky.
DO Get Smart with Your Watering
Monitor your soil moisture to make sure your plants stay healthy through the summer. Water early morning and late evening, to avoid the water evaporating off in the midday heat.
If you’re travelling or just looking for a means of consistent watering, consider a drip irrigation system or soaker hose, but be ready for hosepipe bans to interrupt those plans too.
DO Monitor Temperature and Humidity
Your greenhouse is a mini-ecosystem, and the temperature and humidity in it will be crucial to the health of your plants. Install a thermometer and a hygrometer, and take some time to research what the plants you’re keeping in your greenhouse need to thrive. Make sure you know the range that you’re aiming for, and be ready with measures to stay in that range if your temperature gets too high and your humidity gets too low. A combination of ventilation, shade, fans and misters will be the route to maintaining excellent growing conditions in your greenhouse.
DO Space Plants Property
An overcrowded greenhouse can lead impede airflow and increase the chances of diseases spreading, and even pests making a home for themselves. As tempting as it may be to squeeze plants into every available gap, it’s important to space your plants out for them to thrive.
OUR BIGGEST “DON’T” S OF SUMMER GREENHOUSE GARDENING
DON’T Overwater
In the heat, it can be tempting to just water more and more, in the hope that it will prevent the soil from drying out. But overwatering can be just as damaging to plans, and in high humidity especially, can lead to root rot. Get the watering balance right, and make sure your plants are in well-drained soil.
DON’T Keep the Greenhouse Sealed All Day
Without the right airflow, your greenhouse will trap excessive heat, and on the hottest days, you’ll be essentially cooking your plants. Make sure you ventilate in the morning, and keep vents open during the day for heat to escape.
DON’T Neglect Plant Pruning
Your attention may be on your garden outside your greenhouse when it comes to pruning, but don’t overlook the need to keep plants pruned in the greenhouse too. Overgrown plants can cause problems by restricting airflow through and around your greenhouse. They also risk harbouring pests, who will find more opportunities to make a home in the overgrown stems, branches and leaves. So it’s worth making pruning a regular part of your greenhouse care this summer.
DON’T Use Heavy Fertilisers in High Heat
However tempting it is to boost growth with fertilisers, in the heat of summer fertilisers can do more damage than good. In the worst cases, it can burn the plants roots, and cause stress to crops. So don’t risk undoing all the hard work you’ve put in to your plants and garden up until now by over-fertilising in the peak of summer.
DON’T Ignore Early Signs of Stress
Keep a careful eye on your plants, and be ready to take action if they are showing signs of stress. Wilting, yellowing and spotting are all signs that your plants are struggling. Don’t wait too long to address these issues. The sooner you can identify the cause of the stress and put measures in place to prevent it, the more chance your plants have of recovering.
Some of these tips may seem hard to keep up with, especially if you’re travelling this summer. Our recommendation is to reach out to neighbours or friends with greenhouses, and offer to help each other when you’re away on summer holiday. You can also ask them to harvest and enjoy any crops that ripen in your absence, so they don’t go to waste and don’t end up attracting pests.
We hope these tips are helpful and that your greenhouse thrives this summer!