Top Tips To Maximise Light Efficiency In Your Greenhouse

A greenhouse is an essential structure for nurseries and other commercial horticultural and agricultural growers, allowing for the nurturing of plants and seeds in a controlled and protected environment. It’s also a wonderful addition to a private garden, enabling the green fingered to grow their own food or plants and flowers to enhance their garden.

A good light source for your greenhouse is crucial to ensure optimum plant growth. Plants convert sunlight into chemical energy in order to thrive, a process called photosynthesis. This means that the better the quality of light they are exposed to, the better the growth rate and quality of the plants. Here are some tips to maximise light efficiency in your greenhouse.

Position your greenhouse carefully

If you are installing a greenhouse in your garden, you may already have a spot in mind for it. However, avoid placing it on the most convenient flat hard surface without first considering the amount of sunlight the location will get. Pick a south-facing spot that receives a good amount of sunlight throughout the day. 

Be aware of any sources of shade, such as tall trees or neighbouring structures that will cast shadows or block light from the greenhouse. Ideally it should be positioned away from anything that will throw shade because even a small amount can reduce sunlight exposure and impact the growing environment. 

Use light-transmitting materials

Greenhouses are traditionally constructed with toughened glass panels fitted into a frame and held in place with glass clamps. However they can be made from other light transmitting materials such as polycarbonate. This is a transparent thermoplastic that’s often used in eyeglasses, car parts, medical devices and lighting fixtures. 

However, many gardeners prefer traditional glass greenhouses, not just because of its aesthetic appeal, but also because of its superior light transmitting properties. Glass is more transparent than polycarbonate, and less prone to fading and discolouration over time. It’s also potentially more durable and it’s easier to replace any damaged panes.

Consider supplementing the natural light

If you cannot avoid some shade on your greenhouse, or you live in an area that is prone to overcast cloudy weather, or you simply want to cultivate plants during the winter months, then you may choose to supplement the natural light source with artificial light. 

It is possible to buy dedicated LED growing lights that are designed to mimic the intensity and rhythms of natural light, aiding maximum growth. LED lights are very energy efficient so you can leave them on for long periods of time without incurring high energy costs. 

Although natural light is the best light source for plants, LED lights are a good solution if you are battling with a gloomy location or weather, or stubborn shaded spots of the greenhouse. 

You may also want to consider placing reflective materials such as white plastic or aluminium foil on some surfaces such as the floor and lower walls. This helps to distribute light more evenly and bounces light back onto the plants. 

Cleaning and maintenance

Keeping your greenhouse clean and well maintained will maximise light efficiency, and also extend the lifespan of your greenhouse. Put a cleaning routine in place, ideally aiming to fully clean and inspect it for damage at least once a month.

Use water and a glass cleaner or diluted white vinegar in a spray bottle to clean the panes of glass. Wipe them over first to remove dust, dirt and algae growth that may have accumulated. Apply the cleaning solution and then remove with a soft cloth or sponge or squeegee. Avoid using abrasive materials that could damage the glass. 

Make sure that your greenhouse is adequately ventilated to prevent the build up of mould, mildew, algae and condensation. Seal any leaks or gaps in the structure or panels as soon as you spot them to avoid damage to the plants from cold air and moisture. 

Regular plant maintenance

Prune and train your plants on a regular basis to ensure maximum light exposure and ensure an equal distribution of light around the greenhouse and to every part of the plant. If a particular plant does not seem to be thriving, try repositioning it or removing wilting foliage to stimulate stronger growth.