Plant out your Tomato this month — conditions are right now.
Growing Calendar
This month: May
Log to journalMove seedlings outside carefully
- •Harden off plants
- •Prepare soil outdoors
- •Space plants correctly
- •Water well after planting
Watch Out For
Blight spreads fast
remove affected leaves immediately and avoid wetting foliage when watering
Irregular watering causes blossom end rot
water consistently and mulch around the base to keep moisture even
Never plant out before frost risk has passed
wait until late May and harden off for 1–2 weeks first
Grown Organically
Every method in this guide works with natural systems — no synthetic chemicals, no shortcuts.
Read our approachCommon Questions
About growing Tomato in the UK
When should I plant tomatoes outside in the UK?
Plant tomatoes outside after the last frost — typically late May to early June in most of the UK. Harden them off for 1–2 weeks first by placing them outside during the day and bringing them in at night.
Should I grow tomatoes in a greenhouse or outside?
Tomatoes fruit best under glass in the UK. Outdoor crops work in warm, sheltered spots in a good summer, but greenhouse plants produce earlier, more reliably, and over a longer season.
How often should I water tomatoes?
Water consistently — roughly every 1–2 days in warm weather for container plants, every 2–3 days for border-grown. Irregular watering causes blossom end rot and skin splitting. Mulch the base to retain moisture.
What is blight and how do I prevent it?
Blight (Phytophthora infestans) causes brown patches on leaves and fruit rot, spreading rapidly in warm, humid conditions. Prevent it by watering at the base (not over leaves), removing affected growth immediately, and growing blight-resistant varieties.
Do I need to pinch out tomato side shoots?
For cordon (single-stem) varieties, yes — remove side shoots from the leaf axils to keep energy directed to the main stem and fruit trusses. Bush and tumbling varieties do not need pinching out.
How and when should I feed tomatoes?
Feed tomatoes in two phases. From planting until the first flowers open, use a balanced liquid feed every two weeks to build a strong plant. Once flowers appear, switch to a high-potassium feed (such as a purpose-made tomato feed or comfrey liquid) and continue weekly until the end of the season. Continuing with a balanced or nitrogen-heavy feed after flowering causes lush leafy plants that produce very little fruit.
I can see ants running up my plant stems — should I be concerned?
Yes — ants on plant stems in spring and early summer are almost always a sign that an aphid colony is already present nearby. Ants farm aphids for their sweet honeydew secretions, and actively protect the colony from natural predators like ladybirds and lacewings. If you see ants running up a stem, check the growing tips and the undersides of the youngest leaves immediately. Look for clusters of small soft-bodied insects — black, green or grey depending on the species. Catching the colony early makes a huge difference: remove affected leaves and bin them (do not compost), then check again every two to three days. Do not squash the ants themselves — address the aphids and the ants will leave once their food source is gone.
Member guides
There's more to growing Tomato than this guide covers.
Seasonal reminders, deeper guides, and the small adjustments that change a harvest.
