Welcome back to our series on growing tomatoes from seed, have a look at the care of tomato seedlings if you missed the previous article. As I explained, I tend to transplant seedlings into gradually larger pots until they are ready for their final location.
If the tomato variety is dwarf and to be grown in small containers or hanging baskets, seedlings can be transplanted into their final pots when a few inches tall. Ensure that the containers are well drained, by adding a few pebbles or slates at the bottom, whilst maintaining the ability to conserve moisture; check that the lining is secure and perhaps add water crystals. The eventual size of the plants and the size of the container will determine how many plants per pot or basket. Pretty flowers and herbs can also be planted with tomatoes in a hanging basket for an attractive display, such as lobelia or thyme (I will talk about companion planting in a future post). Keep pots indoors at first and then acclimatise them to their final growing location. If the pot is to be kept outdoors ultimately, take them out on warmer days and bring them in at night to protect from frost until the weather is milder.
If your tomato plants will be grown outdoors or in large pots, wait until the plant is about 12 inches tall. When transplanting to their final position, do so in the evening or on an overcast day. When seedlings are small and the weather is still chilly at night, a home-made cloche can be made from a clear plastic soft drinks bottle – cut the bottle so that the open end is at the top for ventilation. Remove cloches when the days are sunny and warm to prevent extreme temperatures.
Indeterminate tomato plants for greenhouse use will need large pots, a minimum of 10 litres, about the size of shop flower buckets. Tall tomato plants in smaller containers are unstable and need frequent watering. I do not tend to use commercial growing bags as I find that they are too small for the often recommended number of plants. They are also very shallow so a great tip is to use larger pots, cut open at the bottom and to sink them into the growing bag so that the plants have a larger area to grow. Some gardeners grow tomatoes in a bed within the greenhouse but bear in mind that diseases can be harboured within the soil and it is best to change it every couple of years at least. I will discuss tomato problems and disease in a later post.
When transplanting, plant the base of the stem under the soil, remove any lower leaves that would be buried. Further roots will grow from the stem, often visible as “pimples”, and help to anchor the plant for stability. When in its final pot, use bamboo canes and string for support, perhaps attached to the side of the greenhouse and attach the main stem.
I always add a few small stones at the bottom of pots for drainage and weight before adding multi-purpose compost. Egg shells also make excellent drainage material as well as providing calcium, as I will explain when discussing nutrients in a future post. At this point compost will supply all of the required nutrients so you will not need to feed the plants until they are more mature. An extra layer of pebbles or mulch at the top of the pot can help to conserve moisture.
Next time, I will be talking about companion planting, so that you can choose which plants to grow with your tomatoes so why not subscribe to our blog and be first to know when it’s published?.