Tomato Seeds in Ireland
Tomatoes are the crop most Irish gardeners try first and the one most often disappointed by, because almost every sowing date printed on a seed packet is written for southern England. This page gives the dates that work here, the varieties that actually ripen in an Irish summer, and where to buy the seed in Ireland.
Sowing and harvest calendar for Ireland
Months shaded below are the reliable windows for Irish conditions.
Quick facts
- Botanical name
- Solanum lycopersicum
- Difficulty
- Moderate
- Hardiness
- Tender, no frost tolerance
- In Ireland
- Much better under cover
- Germination
- 7 to 14 days at 18 to 25C
- Sowing depth
- 5mm
- Spacing
- 45cm apart, 75cm between rows
- Position
- Full sun
- Containers
- Grows well in pots
- Sowing to harvest
- 16 to 20 weeks
- Harvest
- July to October
Sowing depth and spacing
Drawn to scale from the figures in this guide.
How deep, seen from the side
How far apart, seen from above
The best tomato varieties for Irish gardens
Picked for how they perform in a cool, damp, short summer rather than for catalogue photos.
Gardener's Delight
Open pollinated / Cherry, cordon
The safest first tomato for an Irish garden, and still one of the best tasting.
Growing notes and stockistsSungold F1
AGMF1 hybrid / Cherry, cordon
The best tasting tomato most people will ever eat, and worth the hybrid price.
Growing notes and stockistsShirley F1
AGMF1 hybrid / Medium salad, cordon
The variety to grow if your greenhouse is unheated and your summer is unreliable.
Growing notes and stockistsAlicante
Open pollinated / Medium salad, cordon
The most flexible old variety here, happy in a greenhouse or a sheltered outdoor bed.
Growing notes and stockistsMoneymaker
Open pollinated / Medium salad, cordon
Dependable and cheap, but there are better tasting varieties for the same effort.
Growing notes and stockistsHow to sow tomato seeds
Fill a small pot or seed tray with fine seed compost, firm it lightly, and water it before you sow rather than after. Space the seeds about 2cm apart, cover with 5mm of compost or vermiculite, and keep them somewhere that stays between 18 and 25C. An airing cupboard works for the first few days, a heated propagator works better, and a cold windowsill in an Irish February does not work at all.
Seedlings appear in 7 to 14 days. The moment the first shoots break the surface, move them into the brightest place you have. This is the step that decides whether you get sturdy plants or pale stretched ones, and it is the step most people miss because germination happens in the dark.
When each seedling has its first pair of true leaves, the jagged ones that follow the smooth seed leaves, prick them out into individual 9cm pots. Handle them by a leaf, never the stem, and set them deep so the seed leaves sit just above the compost. Tomatoes root along a buried stem, so deep planting produces a stronger plant.
Growing on in Irish conditions
Pot on into 2 litre pots as the roots fill the 9cm ones, and keep the plants growing steadily. A checked tomato plant, one that has been cold, dry or starved, rarely catches up.
Plants can go into their final position under cover from mid-May, or outdoors once the last frost has passed, which means late April on the south coast, mid-May for most of the country, and the end of May inland and in the north west. Harden outdoor plants off over a week before they go out for good.
Final positions should be a 30cm pot, a growbag with two plants rather than the three the bag suggests, or open greenhouse soil. Support cordon varieties with a cane or a string run to the roof, and pinch out the shoots that appear in the joint between the main stem and each leaf, every week, while they are small.
Feed with a high potash tomato feed once the first truss has set fruit, and water consistently. Irregular watering causes both blossom end rot and split skins, and in a hot greenhouse in July that can mean watering twice a day.
By mid-July, stop the plant by pinching out the growing tip two leaves above the top truss. Under cover allow five or six trusses, outdoors allow four. Anything set after that will not ripen before the light goes in September, and it steals resources from fruit that would have.
Harvesting
Pick when the fruit is fully coloured and comes away with a gentle twist. Tomatoes ripen from the truss nearest the ground upwards, so expect the first ripe fruit in July under cover and August outdoors.
Never refrigerate a tomato you intend to eat soon. Cold destroys the aroma compounds that make a home-grown tomato worth the trouble in the first place.
At the end of the season, usually mid-October under cover, pick everything that remains. Ripen green tomatoes indoors in a paper bag with a banana, or turn the hardest ones into chutney.
What goes wrong with tomatoes in Ireland
Blight
Signs: Brown patches on leaves that spread fast, dark leathery marks on green fruit, whole plant collapsing within days during warm humid weather.
What to do: Blight arrives on the wind most Irish Augusts. Grow under cover where rain cannot sit on the leaves, water the soil rather than the plant, keep the greenhouse ventilated, and pick every fruit at the first sign. Blight-resistant varieties such as Crimson Crush are the only reliable option outdoors.
Fruit will not ripen
Signs: Trusses of full-size green fruit still hard in late September.
What to do: Usually too many trusses for the season length. Stop cordon plants at four trusses outdoors or six under cover by mid-July, remove leaves shading the fruit, and bring the last green tomatoes indoors to ripen beside a banana.
Blossom end rot
Signs: A sunken dark leathery patch on the base of the fruit, worst on plum and cherry types in containers.
What to do: This is irregular watering, not a disease. Calcium moves with water, so a plant that dries out cannot deliver it to the fruit. Water little and often rather than flooding a bone-dry pot, and use a bigger container than looks necessary.
Leggy pale seedlings
Signs: Seedlings stretching towards the window with long weak stems.
What to do: Irish February light is too weak for a windowsill sowing. Either wait until mid-March, or use a grow light. Leggy tomato seedlings can be rescued by potting them on deeply, burying the bare stem, which then roots along its length.
Whitefly under cover
Signs: Clouds of tiny white insects rising when you brush the plants, sticky leaves.
What to do: Hang yellow sticky traps early, before numbers build. In a warm greenhouse the parasitic wasp Encarsia formosa works well and is sold by Irish suppliers. French marigolds planted between the tomatoes genuinely help.
Where to buy tomato seeds in Ireland
Irish suppliers that stock this, so postage stays domestic and seed arrives in time to sow. These are plain links, not paid placements.
Order online
- Brown Envelope Seeds Irish Over 60 tomato varieties, organic seed grown in West Cork Grows and saves its own certified organic seed in West Cork, so the varieties are already adapted to Irish conditions. Visit Brown Envelope Seeds , Co. Cork
- Quickcrop Irish Tomatoes, peppers and chillies, with sowing months on every listing Ballymote based, lists sowing and harvest months per product and ships across Ireland. Visit Quickcrop , Co. Sligo
- Fruit Hill Farm Irish Certified organic and biodynamic tomato seed Bantry based supplier to Ireland's commercial organic growers. Certified organic and biodynamic seed, mail order only. Visit Fruit Hill Farm , Co. Cork
- Seedaholic Irish Heirloom range with unusually detailed packet notes Family run in Clonbur since 2005, deep heirloom range with detailed growing notes on every packet. Visit Seedaholic , Co. Galway
Garden centres and mixed retailers
- Mr Middleton Irish The familiar named varieties, posted from Dublin Mail order arm of a long established Mary Street shop, carries the familiar named varieties the organic specialists skip. Visit Mr Middleton , Co. Dublin
- The Organic Centre Irish Organic tomato seed from Rossinver, Co. Leitrim Registered Irish charity at Rossinver with a 19 acre demonstration garden behind the seed catalogue. Visit The Organic Centre , Co. Leitrim
Common questions
When should I sow tomato seeds in Ireland?
Mid-March is the sweet spot for most Irish gardeners. Sow in February only if you have a heated propagator and a grow light, because natural light levels here in February will produce weak, stretched seedlings. If the plants are going outdoors rather than into a greenhouse, early April is soon enough, since they cannot go out until the frosts have finished anyway.
Can you grow tomatoes outdoors in Ireland?
Yes, but it is the harder route and some years it fails. You need a sheltered spot in full sun, a bush or determinate variety that crops early, and ideally blight resistance. Coastal Cork, Wexford and Dublin do better than the midlands or the north west. Under a polytunnel or greenhouse the same plant will crop roughly twice as long and twice as heavily.
Do I need a greenhouse to grow tomatoes in Ireland?
Not strictly, but it changes the odds enormously. A greenhouse or polytunnel keeps rain off the leaves, which is the single biggest factor in avoiding blight, and adds the warmth that ripens fruit. A cheap plastic growhouse against a south-facing wall, or even a sunny porch, gives most of the benefit for a couple of plants.
How many tomato plants do I need?
Two or three cordon plants under cover will keep a household in tomatoes through late summer, since a well-grown plant produces around 4kg of fruit. Cherry varieties give more fruit by number but less by weight. Most gardeners sow far more seed than they need, so a packet lasts several years if kept cool and dry.
What is the difference between cordon and bush tomatoes?
Cordon, also called indeterminate or vine, grow as a single tall stem, need side shoots pinched out and support, and crop over a long season. They suit greenhouses. Bush, also called determinate, sprawl, need no pinching, and produce most of their crop at once, which suits containers, hanging baskets and outdoor growing where the season is short.
Are F1 tomato seeds worth the extra money?
For Irish conditions, often yes. F1 varieties bred for cool greenhouses, such as Shirley, set fruit at lower temperatures and carry more disease resistance than old open-pollinated types. The trade-off is that you cannot save seed true to type, so if seed saving matters to you, choose an open-pollinated variety like Gardener's Delight instead.