For cherry varieties (apart from Tumbler and other bush varieties) stop the plants (pinch out the growing points) in the first week of September; for all other types stop them in early August. It may help to ripen the remaining fruit if you remove some of the older leaves which are shading them. Don’t do this in very hot conditions as the excessive heat may make the fruit soft.
Picking tomatoes
With cherry varieties you should pick your first ripe tomatoes when they are flowering on the 6th truss; for larger-fruited types you’ll have to wait until the 9th truss flowers. You might get a new truss approximately every ten days, so if you plant in mid May with the first truss in flower, you might expect your first pick sometime in the first half of July for cherry tomatoes and about a month later for larger varieties. In the meantime, buy British-grown tomatoes for the best flavour.
Supporting and training tomatoes
Commercial growers support their plants by twisting the stems around very long strings – outdoors it is easier to use canes or poles. Remove the sideshoots whilst they are small -see our video on how to do this – Twisting Tomatoes – (training and side-shooting tomatoes).
Sowing tomatoes
Sow about 25% more seeds than you want plants, to allow for some losses and so you can select the strongest seedlings. You will need some clean seed trays. Those with individual cells work well, but you can also use suitable food packaging if you make sure there are holes for drainage. The trays need to be at least 3cm deep. Fill them with good quality seed compost – look out for Gardening Which Best Buys (and Don’t Buys!) Make sure the surface is level and firm. Sow the seeds about 3cm apart and cover with about 4mm of compost. Water them using a watering can with a fine rose. Cover with clear plastic or a sheet of glass. Put them somewhere warm to germinate: 20 – 25°C is ideal. After about 5 – 7 days the seeds will have started to germinate. They must be uncovered immediately and put somewhere with plenty of light, but still ideally 20°C (minimum 16°C). It may be necessary to spray the seedlings with a fine mist to help the emerging seedlings shed their seed coats.
Planting & spacing tomatoes
Spacing
Tomatoes need about 0.4 sq m (4 square feet) per plant, so you can plant them 60cm X 60cm (2ft X 2ft) or 46cm (18 inches) between in the row and 87cm (21/2 ft) between rows.
Planting
By the time conditions are suitable for planting, you may be able to see the first truss in bud or just opening. Your plants may need a small cane to support them if they start to flop over. It is very important to remove the first truss shoot early so that you get a strong first truss. This is a side-shoot that grows in the axil below the first truss. For details of how to remove side-shoots see our helpful video on YouTube: Twisting Tomatoes – (training and side-shooting tomatoes).
Make a hole with a trowel, and plant as deep as possible without burying any of the leaves, or covering the graft union (if your plants are grafted).
To graft or not to graft tomatoes?
To graft or not graft for tomato growing?
To graft or not graft?
My advice is that grafted plants are worthwhile if you are growing tomatoes in the same soil year after year (usually in a greenhouse). You are unlikely to see a benefit from the disease-resistant rootstock if you are growing in grow-bags or containers using fresh growing media. You may still benefit from the extra vigour resulting in an earlier first pick or an extended harvest period at the end of the season. If you buy grafted seedlings, make sure the graft is above the surface of the compost when you pot them up or plant them. If you don’t, the scion may produce adventitious roots and you will lose the benefit of the rootstock.
Pollination and setting of tomatoes
In commercial greenhouses growers use bumble bees to pollinate their crops. If your plants are outdoors, there should be enough wind and insect activity for pollination. In the greenhouse, it is a good idea to gently shake the strings or other supports around mid day, or tap the trusses which have flowers open. If the weather is very hot and dry, it may help to water the paths in order to increase the humidity and cool the greenhouse.
Growing tomatoes to planting stage
Growing to planting stage
Tomato plants need as much light as possible, so keep them in a conservatory or on a sunny windowsill (but don’t leave them behind the curtains). On warm, sunny days you can put them outside, but don’t forget to bring them inside at night. Ideal temperatures at this stage are 15°C at night and 20°C minimum during the day.
Growing to planting stage
Tomato plants need as much light as possible, so keep them in a conservatory or on a sunny windowsill (but don’t leave them behind the curtains). On warm, sunny days you can put them outside, but don’t forget to bring them inside at night. Ideal temperatures at this stage are 15°C at night and 20°C minimum during the day.
Your plants may need to stay in their pots for several weeks until the weather is suitable for planting. Space them so the leaves don’t overlap. They may need liquid feeding, especially if you have used seed compost to pot them up (it is usually lower in nutrients than potting compost). Use a proprietary high potash tomato feed made up according to the label recommendations. Typically they will need feeding from about 4th true leaf stage, but if the bottom leaves start to turn yellow or purple, this can be a sign that they are running out of nutrients (purplish tints can also be due to low temperature).
Pricking-out tomatoes
Although you can successfully plant the seedlings directly into the soil, we recommend that you pot them on first.
You will need one pot for every seedling – at this stage allow about 10% extra. Pots with a diameter of 13cm (volume 1 litre) are a good size. You can use the same compost that you used for sowing, but you may need to liquid feed the plants if you are growing them for several weeks in the pots.
Fill the pots to the brim as the compost will settle once it is watered. Make a hole deep enough to take the roots without curling. Plant them so that the cotyledons are just above the surface of the compost. Do not firm them in – water them in gently. Check them every day and give them a light watering as required. Make sure the leaves are dry before evening, as the seedlings are more likely to ‘damp off’ (rot) if they go to bed with wet leaves.