How to Grow Tomato Plants from Seed to Harvest

5 simple steps on growing tomato plants

Tomato Plant

Growing tomato plants is relatively easy, they can be grown almost anywhere that is warm and slightly damp. Providing you supply them with adequate sunlight and water, with a little patience you can be producing an abundance of fresh juicy fruits.  They can be grown in a small area of the garden or greenhouse. They can also be grown in pots on balconies or patios, or directly from a grow bag.

There is a variety of plants to choose from when growing tomato plants, with a variety of shapes, sizes, colours and most importantly taste.  From beefsteak to cherry, pear to heirloom, for a first time grower, or indeed any grower for that matter, I would recommend selecting a variety of plants to grow.



Here is 5 steps to growing tomato plants.


1-      Starting Seedlings

(if starting from tomato plants, please go to 2.)

If you are starting tomatoes from seedling then the first thing to ensure is that the pots or containers you are planting the seeds in are clean and disinfected.

Tomato seeds, like most seeds, prefer a soilless mix to be planted in rather than soil. Soilless mix is predominantly sphagnum peat moss. The benefits to using a soilless mix are it greatly reduces the chance of disease spores, bacteria or plant eating insects interfering. It also provides better drainage than soil, and is generally lighter.

Ensure the soilless mix, or soil is damp, then break up with your hands (making sure they are clean).  Fill the pots with 2/3 full with the mix, then tap the mix to help it settle and push down gently with your hands.

Plant your seeds in the container, using around three times as many seeds as you expect to grow, since some will not germinate, and of the ones that do not all of them will survive.

Cover the seeds with a little more dampened mix and again press down gently with your hand. Although the mix is already damp it is a good idea to lightly water the seeds to ensure a good contact between the seed and the mix.

They are now ready to be covered with a clear plastic sheet, or alternatively put into a clear plastic bag leaving it slightly open. This keeps in the heat and moisture. The seeds can then be stored in a warm, draft-free place. Ensure that the potting mix stays damp but not wet.

Make sure to check them daily and when you first see a seedling emerging, remove the plastic sheet or bag and move into indirect light. As they develop the seedlings need around 12-18 hours of light a day.

As the seedlings begin to grow they will develop small green leaves. This is when the seedlings begin photosynthesising. If you are using a soilless mix, you will need to give your seedlings supplemental feeding at this point, either a balanced fertiliser or one that’s high in nitrogen and potassium should work well.

When the seedlings reach a couple of inches tall and have a few leaves, it is usually best to transfer them to larger pots allowing the roots to develop further. This is called ‘potting up’. At this stage, when growing tomato plants, try to allow a container for each plant giving them plenty of room.



2-      Before planting

To strengthen the plants before potting into larger containers or outside, it is recommended that you move the plants into a shaded area from time to time, maybe for an hour or so. It also seems tomato plants need to sway in the breeze, so they can develop strong stems Putting a fan on them for 5-10 minutes twice a day usually works.

Before planting the tomato plants outside ensure the soil is well fertilised, and damp.  It is a great idea to cover the area with a black or red plastic sheet up to a couple of weeks before planting. It’s amazing how much of a difference this makes. Trapping those extra few degrees results in earlier tomatoes, so it is well worth it.

Position stakes and cages to help support the plants as they grow.



3-      Planting

Tomato plants should only be planted outside when there is no chance of any frost, in a sunny, sheltered area.  They should be around 18 to 36 inches apart.

When planting tomato plants be sure to bury them.  Well over 50% of the plant should be buried; it doesn’t matter if you bury some of the lower leaves too. Tomato plants are able to grow roots along their stems giving the plant a nice development boost. If growing in grow bags this means you can lay the stems along horizontally in the bags, the plants will adjust their growing direction accordingly.

After planting, water all the plants well with warm water, to prevent the shock of moving.



4-      Growing

For the first two weeks water every day, ideally with slightly warm water. Little and often is the key, keeping the plants damp but not wet.

After the first two or three weeks, mulch to retain moisture. Mulch is a material that is spread over the soil, often made up of straw, dried grass, pine needles and compost.  As well as retaining moisture in the ground, mulch helps to prevent weeds, keeps the soil cooler, enhances the fertility of the soil as it decomposes and generally makes the bed look more attractive.

After the first couple of weeks, water less frequently but still ensuring soil stays moist, but definitely not wet as this encourages diseases. If the tomatoes are outside keep an eye on when it’s raining and how much water the plants are getting. Some days you may need to water the plants a lot, however you may go a few days without having to water the tomato plants at all.

As they grow attach the plants to the stakes and cages to promote healthy growth. Shake the plants each week to help distribute pollen and promote growth.

When the tomato plants reach around 3 feet tall its best to remove the leaves from the bottom 1 foot of the plant. These are the leaves that receive the least sunlight and they are usually the first leaves to develop fungus problems.

Prune plants pinching out ‘suckers’. These are the little sprouts that develop between the joins of two branches. These don’t produce any fruit and drain the plant. You can thin the leaves out a little but be careful, it’s also the leaves that develop the sugars which gives the flavour to your tomatoes.

Around two weeks before you plan to pick any tomatoes, its best to fertilise the tomato plants.  Fertilise again around two weeks after first pickings. When selecting a fertiliser be sure to look for a vegetable fertiliser for stimulating fruit, not a lawn fertiliser which helps the growth of stems and leaves.



5-      Fruiting

When growing tomato plants, the fruits begin small and green, but as it grows and begins to ripen so do the colours, most commonly a vibrant shade of red. Ripeness is usually defined as having a slight softness.

Tomatoes can be picked early and left to ripen indoors, however they usually attain their best taste when left to ripen on the vine.

Never refrigerate tomatoes as this spoils the flavour and texture of the fruit. Store in a cool, dry place.

There you have it, 5 steps to growing tomato plants. 


Interested in Growing a Herb Garden? Check out 10 essential herbs and how to grow them, from seed to plate here.