May
2023
DO YOU HAVE TO BALLET DANCE AROUND THE PLANTS IN YOUR MAY GREENHOUSE?
By Linda Lane
Managing Director of Griffin Glasshouses
You need to be a ballet dancer to safely manoeuvre around my green house in May as every inch of
space on staging, shelves and even the floor is taken up with pots, hanging baskets and trays of
tomatoes and vegetable plants, all waiting for the risk of frost to pass so they can be planted
outside.
May is an extraordinarily busy time in the greenhouse. Plants have to be watered, shaded and weed
and pest checked. The cold frame is full to overflowing and every morning, before going to the
office, I take out various trays and pots and put them on tables outside the greenhouse to slowly
harden off. Then it’s a case of listening to the weather forecast to check whether I need to bring
them back in at night.
The May sun is getting very warm and it is absolutely essential to keep a cooling air flow throughout
the greenhouse – in the day time. But close up most windows and all doors at night until you are
satisfied the frost risk has passed – but keep listening to the weather forecast!
I plant tomatoes directly into the soil in my greenhouse and will do this early in May. The first yellow
flowers should appear fairly quickly and then its time to start regular feeding and removing side
shoots. Tying them to supports is vital but remember you are tying the plants to the support. So if
using horticultural string, firmly tie it to the cane first and then enclose the loose ends around the
plant and tie it into position, leaving sufficient space for the plant to grow and expand. Do not tie
the plant directly to the cane.
If you prefer to tie the tomato plants to vertical string, remember to twist the string around the stem
of the plant – not the other way round.
This also applies to peppers – both sweet and hot, cucumbers and aubergines. I plants aubergines in
pots and, once in flower, take them outside to increase the chances of pollination. I take them in
again at nights.
As the available space in the greenhouse increased with the migration of the plants outside, water
the floors in really hot days to help cool things down and increase humidity.
It isn’t just tomato plants that require feeding. Most vegetable and fruit plants cannot obtain
sufficient nutrient without additional help. I always have several cans of water in the greenhouse so
they are at an appropriate temperature. On hot days remember to check whether the water will be
too warm for the plants.
Maintain the greenhouse in a clean state and always remove weeded plants, fallen leaves and other
rubbish. If you have space, do put a comfortable chair in a shaded area of the greenhouse. It is a
great place to relax and take stock on a warm afternoon.
Happy Gardening
Linda