How to grow tomatoes (without a greenhouse!)

July 30, 2013
Author: Hannah

Eden horticulturalist Duana Pearson shares her top tips on how to grow tomatoes outside, when you don’t have the luxury of a greenhouse – including planting from them seed, treating tomato blight, and making your own tomato feed using comfrey leaves.

There really is nothing better than home grown tomatoes. Great news for those with greenhouses, but what about the rest of us? Well here at Eden we grow plenty of tomatoes outside, sometimes with fruit still ripening into November.

With a sunny spot in your garden, space for some pots or a grow bag and a minimum temperature of 10 degrees Celsius, you can grow tomatoes too.

Home grown tomatoes

Which tomatoes to grow

Did you know, that when tomatoes (Solanum lycopersicum) were introduced to Britain in the 16th century from their native South America, they were branded inedible because of their close resemblance to the toxic, deadly nightshade? Since then, all sorts of gorgeous-tasting varieties have been cultivated…

When choosing a tomato variety, go for one that’s not only blight-resistant, but suitable for the spot it’s to grow in. For taller growing (cordon) varieties, try Gardener’s Delight, Chadwick Cherry, Money Maker, Sweet Olive, or Alicante.

For pots or hanging baskets, try bush or tumbling varieties such as Tumbling Tom, Garden Pearl, or Tumbler.

You might even consider heritage or organic varieties, tomatillos (golf-ball-sized fruits surrounded by a papery husk, which have a tart flavour and are a staple of Mexican cuisine), or beefsteaks – great for cooking – and showing off!

How to grow tomatoes

From seed
If you’ve time to grow them from seed…

  1. Sow the seeds indoors in March or April.
  2. Keep your seedlings moist and in a sunny position.
  3. Plant out, two feet apart, in a sunny spot after risk of frost has passed. For example, in June.

As plants
Once your tomato plants are in the soil…

  1. Cordon varieties (as opposed to tumbling or bush plants) need staking well. Keep tying in as the plants grow.
  2. Taller growing tomato plants also require you to pinch out side shoots carefully to create one strong main stem and encourage fruiting. Side shoots are the growths that appear where the main leaves join the stem. Try to limit the plant to four to five trusses, then pinch the tip of the side shoot. This will probably give a height of about five feet. This will encourage the plant to put energy into ripening fruits, and should still give you a good yield.
  3. Feed when fruits start appearing. Many tomato feeds are widely available – or you could make your own using comfrey leaves (recipe below).
  4. Harvest from July, as the fruits turn red.

Tomatoes growing at the Eden ProjectDuana’s top tips

  • Even watering, little and often, will help prevent fruit from splitting.
  • Plant tomatoes with basil for a delicious combination. It’s also said to improve the flavour of the tomatoes as they grow.
  • We use homemade comfrey tea to feed our tomatoes. To make this, top up one full bucket of comfrey with water and leave to steep for a few days. Or you can leave it for longer and then dilute the ‘tea’ with water. Sieve it out and apply neat with a watering can. This is best done the same day you water the tomato plants.
  • If you get to October or November and still have fruits on your tomato plants that don’t look like they are going to ripen, harvest them all and make green tomato chutney.

Dealing with tomato blight

Blight, Phytophthora infestans, is probably the biggest concern when growing tomatoes. Spores can survive in infected seeds or be blown in from miles away, but will only affect a plant if landing on wet foliage or fruit. It starts as ugly, brown blotches on leaves, but can quickly spread to fruit and other plants.

  1. Pick resistant varieties – but be aware this may only delay any infection.
  2. Use a reputable supplier and don’t save seed from infected plants.
  3. Change where you put plants in the Solanaceae family (including aubergines, potatoes, peppers and petunias)  every few years. This is known as ‘crop rotation’.
  4. Allow good air movement around plants. You can do this by spacing them well apart, staking well, and removing side and old shoots.
  5. When watering, try to water in the morning. Make sure you water only the soil, rather than the foliage itself.
  6. In early stages of a blight infection, remove diseased leaves.
  7. Use copper sulphate solution to help protect healthy foliage.
  8. Sign up to the free Blight Watch service, which sends alerts about blight-risk periods, based on temperature and humidity.

On the vegetable plot at Eden

We planted our tomatoes out last month. They’re growing down in the garden by the Bakery, and we’ll be passing some of them on to the chefs. We’re also busy tackling sawfly on our currants and gooseberries – using foxglove tea!

If you’d like to learn more about gardening from Eden horticulturalists, join us for one of our one-day gardening courses – or do all eight and get a qualification!

Thanks to Poppy/hddod for the photo.

Gift guides, Horticulture

11 responses to How to grow tomatoes (without a greenhouse!)

  1. Andrina Watt says:

    First year growing tomotoes they are in big pita outside.. Have a lot of fruit and some really large ones but most haven’t turned red!. The small ones have but large fruit are rock hard and green.. Have removed excess leaves to help but still no change.. Thought about covering with clear plastic bags to help with heat but unsure.. Any help would be fab! Thanx :-)

  2. Hannah says:

    Removing excess leaves from the base of the plant certainly helps, because it allows sunlight to reach and ripen the fruits. Another reason for slow ripening tomatoes is perhaps that they are larger varieties, which are slower to mature. Another (unlikely) possibility is greenback disease. However, this would typically affect all the fruit – and tomatoes usually still try to ripen, except around the stalk and shoulder of the fruit.
    As your tomatoes are otherwise well and maturing, we think the best thing to do would be to cut the tomatoes which aren’t ripening from the plant and either use them green or place them on a sunny windowsill to see if they will ripen. Placing ripe tomatoes with green ones should encourage ripening.
    Avoid plastic bags as they are really going to encourage sweaty conditions, which will only really help mould.

  3. Wandera K. Desire says:

    Thanks for the advise but how better can one plant tomatoes in Kampala – Uganda for better yields? The advise you are giving is derived from your European study while here in Uganda we are along the Equator line our climate is too different & sunny/rainy at times compared to one in Europe.

  4. edegbe emmanuel says:

    how do i get tomatoe seeds to plant?

  5. Hannah says:

    All good garden centres should sell tomato seeds. We also sell some in our online shop:

  6. NYALO ERICK says:

    thanks, i got a lot from you people. but how can i get the seeds and if more advice can be posted to me through my email i will be greatful. bravo to you.

  7. Hannah says:

    All good garden centres should sell tomato seeds. We also sell some in our online shop:

  8. kinja kenneth murimi says:

    keep up am requesting for help on how to grow tomatoes in uganda western region bushenyi-ishaka have already started.

  9. Jody says:

    I have tumbling toms, gardener’s delight, Roma and moneymaker toms growing outside in containers, they have all got plenty of fruit but aren’t turning red, and the temp here is dropping to 8•c at night! What can I do to help them survive to ripening?

  10. noha says:

    First time to grow tomatoes for me, I have cherry tomato plant in pots outside in our patio as I have no garden. it has been doing great till last week. The fruits are turning red but all the stems and leaves are wilting and dying, we had a bad week of rain showers that the pots were flooded with water but I’ve emptied them from the excess water and even took all the soil out of pots and aired for a couple of days before putting it back again but nothing seems to work, any advice please??

  11. Hannah says:

    One of our horticulturalists Shirley Walker says: I doubt it would have been the rain unless the plants were standing in water for a long time. Don’t stand your pots on saucers – they need to be able to drain freely. A lot of rain would have washed all the nutrients out of the soil so they would need to be fed – a liquid tomato feed should be used once a week. At the end of the season it is normal for leaves to turn yellow. We had a few cold nights a couple of weeks ago, so that won’t have helped.

Leave a Reply

Your email address will not be published. Required fields are marked *

  • Categories

  • Tags

  • Archives