It’s that time of year when everyone has the gardening bug. For some people that means cutting the grass once a month, but for those of us avid gardeners it can get a lot more obsessive. And at some point in every obsessive gardener’s life, they start greenhouse growing. The power of protecting your plants from the weather and controlling the temperature means you can get a much higher yield from a greenhouse crop, which is why it is so inviting. But it’s also quite easy to get it wrong. If you don’t pay enough attention to your greenhouse conditions, you can end up killing all your plants before you harvest.

We’ve come up with a few tips to help you make the most of your greenhouse -

Get The Temperature Right

This is one of the greenhouse grower’s biggest challenges. In the UK, temperatures are capable of changing rapidly and unexpectedly which can leave gardeners with a host of dead crops. The best way to combat this is constant vigilance - keeping an eye on the weather reports and preparing for the worst. But that’s not always possible and you should have a backup plan in place too.

Here are some ways you can protect your greenhouse crops -


  • Automatic ventilation - opens when the greenhouse temperature hits a certain point and shuts again when it has cooled down. Surprisingly inexpensive, with cheap versions available at below £50.
  • Greenhouse shading - this can range from simply painting your greenhouse panels to automatic shades that shut in the sunlight.


  • Insulate with bubble wrap - the beauty of insulating your greenhouse with bubble wrap is that it still lets in some of the light from the sun.
  • Greenhouse heating system - a more reliable, but more expensive option is to buy an automatic heater.
  • Horticultural fleece - on really cold nights, using a fleece to wrap your vulnerable plants could make all the difference.

Use Plastic Sheeting Instead Of Windows

Traditionally, greenhouses were made with glass. However, polycarbonate actually makes for a much more suitable material for the greenhouse windows. Firstly, it’s much more durable than glass and resistant to breakages, and it is less affected by sunlight, snow and rain so it lasts much longer. The other really useful advantage is that it doesn’t let as much UV light through. UV light damages plant’s DNA, proteins, lipids and membranes which means they can be killed off by too much exposure to sunlight.

Polycarbonate windows are also really easy to cut to shape which makes them perfect for making more inventive greenhouse structures. Check out Cut My Plastic for affordable greenhouse windows and for unwanted plastic you need to recycle Kwiksweep provides a green service that reduces the amount of waste going to landfills. 

Don’t Underestimate The Power Of Soil

Your success as a gardener will rest or fall on the quality of your soil. Healthy, nutrient-rich soil, will make a huge difference to your yield. Before you plant anything in your greenhouse make sure you have properly prepared your soil, mixed it with high-quality compost and given it time to breathe.

Keep The Plants Watered

Unlike your outdoor crops, your greenhouse plants aren’t getting any rainwater, so you need to be vigilant in keeping them watered. It’s too complicated to work out exactly how much water each plant needs and exactly when they need watering, so instead, just keep to a regular watering routine. Start with an overestimate of how much water they need (say, every morning and night) and then test to see if you can back off a bit. Feel the top of the plant’s soil and if it is dry then it needs more water.

If you are looking for a more high-tech solution, UKh2o suggest investing in an automatic irrigation system - where you fill the reservoir and programme the timer to water as much as is needed.

Maintain An Insect Patrol

Unwanted insects are a greenhouse gardener’s biggest enemy. Slugs, snails and aphids can all find their way into a greenhouse that isn’t properly maintained. You should leave enough space between plants so that you don’t give the critters anywhere to hide (this also gives your plants more space to grow). Also, at the end of the season, take all of the plants out of the greenhouse and give it a thorough clean - this will avoid any insect eggs hatching and also allow the building to air out for the following season.

You don’t have to get rid of all the creatures in the greenhouse, after all it is a suitable habitat for them. So make sure you do the research and find out what you’re looking for before you go evacuating tenants.