Growing tomatoes from seeds is a really simple straight forward process. There are a few basic things you need to consider such as warmth, position, drainage and air circulation that are needed to successfully grow plentiful tomatoes.
Whether you’re new to growing tomatoes or are an old hand, there are a few simple steps you need to think about before you go and buy some seed.
Where am I going to grow my tomatoes? What room do I have? Will my tomatoes be growing in the ground? Am I going to grow my tomatoes in a pot on the patio? These are all important questions to ask yourself before choosing your tomato variety.
What type of tomatoes do I want to grow? There are hundreds of varieties out there in seed form with large tomatoes for slicing, cherry tomatoes that can be eaten whole. The colour range and taste is quite extensive.
This is one of the most important things to consider. Tomatoes come in two main types: Indeterminate which means climbing or rambling and the Determinate or bush tomato, which means they grow to a set size and don’t require as much room.
There are a few basic items that you will require be for you start.
What you use is your own personal choice. Personally, I don’t like paper/cardboard style pots due to problems in sterilizing those style of containers. You may find all sorts of things in the recycle bin like a plastic drink bottle, take away containers, or the seedling punnet from the last trip to the plant nursery. It really doesn’t matter as long as it is clean and sterile and has good drainage holes in the bottom.
Do not use garden soil. I use a good quality vegetable growing potting mix with added fertilizer rather that spending money on a seed raising mix which probably has little nutrients in it. Think about your own body for a moment - without food you’re going to get hungry and not grow well. Seedlings are exactly the same they will be living in that pot for a few weeks.
Sterilize and clean your pots. I do this by washing away any dirt or what ever was in the container before with hot soapy water, then soak the pots in hot water with 5% bleach for 30 minutes or more. Rinse the pots then fill with potting mix, tap the pot on a hard surface to pack the potting mix a little, then add more potting mix to fill the pot.
Poke 3 shallow holes in the potting mix and place 1 seed in each hole, very rarely there is such thing as 100% germination.
Don’t forget, Tomato seeds require warmth to germinate.
This next step is so important - DON’T plant too deep! If you take a look at the seed, you'll notice it is not very thick - probably 1mm at the most. I don’t cover these seeds with potting mix by hand, I use the spray bottle to wash some potting mix over the seed to just cover them. If you see part of the seed that’s great. One of the biggest causes of germination failures is the seed was planted way too deep and the new seedling runs out of energy trying to get out of the ground.
Give the pot a light spray of water twice a day until they start to germinate, then lightly water once daily while they are growing. It is important to keep the seedlings warm and give them plenty of light or they will become leggy quite quickly.
Regardless of whether you are going to plant your seedlings in a large pot or in a garden bed the same rules apply. Good quality garden soil or potting mix is important. It must be well drained and rich in humus and nutrients to get the best out of your tomatoes. If your garden bed is likely to become waterlogged you may need to build up the garden bed to improve drainage as waterlogging can cause root rot and that’s an entry point for all sorts of disease.
When your seedlings become around 15cm tall it is time to plant them out. Unlike other seedlings, Tomato seedlings like to be planted deep. I plant my tomato seedlings around ¾ of the way up to the bottom leaves. The seeding will start to grow additional roots all the way up to ground level so planting them deep gives them a strong root system early in their growing season.
I prefer to plant my tomato seedlings later in the afternoon as the heat is going out of the day to give them the best chance of growing and that way the seedlings won’t get a setback because of heat.
Give them a daily watering for the first week or so while they are settling in. Fertilising your tomatoes is a personal choice. With good soil or potting mix, they don’t require fertilizer at all. Some gardeners like to fertilise when the vine starts to flower. If you’re going to fertilise, use a fertiliser that is suited for tomatoes, low in nitrogen and higher in Phosphorus. It is recommended to use 5-10-5 or a 5-10-10 mixed fertilizer.
Tomatoes generally are a trouble-free plant to grow. Water them consistently a couple of times a week and maybe three times a week in hot, dry weather. Mulch well around your tomato plants, keeping the mulch away from the stem which helps keep weeds away, save moisture and to keep the root zone cool. I stake all of my tomatoes regardless of what height they grow to stop them getting battered around by the wind.
Again, this is a personal choice. I prune the leaves off near the ground for two reasons, the first is stop any water splash on the leaves that may carry a fungus and the second reason is let air flow around the plant. Be careful though, because if you take away too much foliage you risk the fruit becoming sunburnt.
Harvest your tomatoes as they start to colour up and become a little bit softer, leave them too long and you are inviting pests into the yard, birds love a ripe tomato.
Good luck and Happy Gardening