If you are thinking of growing your own tomatoes from seed then firstly I strongly encourage you to try it, it is a really rewarding thing to do, and secondly here is a complete guide on all the stages of growing tomatoes from seed! Enjoy.
Stage 1 New Seedling
This is the stage where your tomato seedlings just start to poke their head above the soil. This photo was taken on the 18th Feb. I start my seedlings inside on a window sill above a radiator, this gives them the heat they need to germinate.
They are tiny little things at this point and are very vulnerable. If I tried to sow these outside in the UK at this time of year they would never germinate to begin with but even if they did the cold weather would soon kill them off.
Stage 2 Established Seedling
The little tomato plant has now turned into a more established seedling. It has developed a few leaves and will also have grown a lot of roots under the soil.
You will want to leave them growing on like this in the same pot for a few weeks yet.
Stage 3 Transplant
The seedling is now strong enough that it can be planted out into a greenhouse or polytunnel. Because it is still spring at this stage in the UK I would not advise planting your tomatoes outside unless you are a lot later in the season.
They will still be vulnerable to any frosts at this stage.
Note that I plant my tomatoes really deep in the soil and I have also taken the lower leaves off the plant. Tomatoes will grow new roots off the main stem, so by planting them deep we make the plant create extra roots. This helps to develop a really strong plant.
Stage 4 Developing Strong Roots
While it may not look like much has happened between the last and this photo the tomato seedling will have been growing lots and lots of strong roots out of its buried stem.
This is all setting the plant up for really strong future growth. It is building a strong foundation now so that it can grow like crazy when the weather warms up a bit.
Stage 5 Established Plant
Look at the amount of growth these tomatoes have put on in a few weeks, they are now at the rapid growth stage where there will grow like mad.
The plants have also started developing side shoots which we need to pinch out to encourage our tomatoes to grow up rather than out.
These are money maker tomatoes so are made to be cordon grown. This just means you grow them vertically up one main shoot.