June is one of my favourite months in the tunnel or greenhouse. The majority of crops are planted by now and the responsibility of watering your seedlings every day is nearly over. You can enjoy tending your crops and observe how they develop. There is also a relatively decent range of crops ready to harvest.

Direct sowing into beds

In June your tunnel or greenhouse is most likely to be full of crops and there is no space for sowing crops direct. Generally you’ll be much better off raising plants in modular trays as you gain at least four weeks of valuable growing space.

Planting into beds in the polytunnel / greenhouse

You can still plant out all your summer crops such as tomatoes, peppers, chillies, aubergines, basil, courgettes, cucumbers, melons, and sweetcorn especially if you have well-established plants. Even if it is on the late side for some of these crops, you will still get a decent yield from them.

Sowing into modules / pots (18–20°C)

You can still sow a range of vegetables into modular trays. There will always be crops harvested, beds cleared and space available. So even if your tunnel or greenhouse is full at present there will be space in four to six weeks when your new transplants are ready to plant.

For planting inside

• Basil (Sweet Genovese) – 4 seeds per cell
• Chinese cabbage (Yuki F1) – 1 seed per cell
• Courgette (Defender F1) – 1 seed per 7cm pot
• Cucumber (Passandra F1 & Styx F1) – 1 seed per 7cm pot
• Coriander, Dill and Chervil – 5 seeds per cell each
• French beans (climbing and dwarf) – 5 seeds per 9cm pot
• Florence fennel (Rondo F1) – 1 seed per cell
• Lettuce (various types) – 1 to 3 seeds per cell
• Pak Choi (Joi Choi) – 1 seed per cell
• Parsley (curly and flat leaf) – 4 seeds per cell
• Scallions (Ishikura Bunching) – 10 seeds per cell

Harvesting

In June you will get a lot of produce from your tunnel or greenhouse:

Beetroot, cabbage, carrots, chervil, coriander, courgette, dill, French beans, kohlrabi, lettuce, peas, potatoes, radish, salads (any), scallions, spinach, strawberries, turnips.

If you are lucky enough and live in a favourable area you may already get some tomatoes and cucumbers. Unfortunately my tomatoes only start to ripen from July onwards.

General greenhouse / polytunnel maintenance

• Water more frequently and more heavily now, probably about two to three times per week.
• Ventilate as much as possible.
• Weekly maintenance for summer crops: side-shooting and training tomatoes, cucumbers and melons. You should also remove the lower discoloured or diseased leaves.
• Keep a watch out for pests, especially whitefly on tomatoes, aphids on salads and fleabeetle on brassica salads.
• Spray aphid susceptible plants with a garlic or seaweed spray every seven to ten days.
• Remove weeds as they would compete with your plants.
• Prick out and pot on plants as necessary.

You can get John’s book Vegetable Growing Month-by-Month here.