The Royal Horticultural Society (RHS) has provided greenhouse owners with a number of hints and tips for the month of May.
With temperatures outside beginning to creep up, it is important to monitor and regulate the heat under glass to avoid scorching or dehydrating the plants.
An application of shade paint to the outside of the glasshouse or the use of blinds on sunny days can stop temperatures becoming too high, while opening doors and vents increases airflow and reduces heat levels.
Those who have started bedding plants early under glass can start thinking about putting them outside now.
However, they should be gently introduced to harden them by exposing them for a few hours at the warmest time of day and gradually increasing their time outside until they are ready to be put in the ground.
It is also important to increase the space between greenhouse plants as they are likely to grow more during the warmer months.
The RHS may be a busy organisation this week as it makes the final preparations for its Chelsea Flower Show in London.