Well, the flowers ARE the tomatoes. It's up to you whether you want to let them become tomatoes, or pinch them off to let the plant use the energy to grow a bit faster. Personal preference, everyone has a different idea of this stuff. What are you growing these in?

you say "One thing I noticed was that pre-potting, there were flowers beginning to grow on the stems." According to some internet sites, they need to be pinched out otherwise I won't get any tomatoes. Is that true? no
in this case as all of your plants are indeterminate and like airbrush and many others believe it is better to remove the first flowers and when transplanting pinch/cut off all but the top 2-4 branches and plant up to 1" below the lowest branch - this allows the plant to grow new root system along the main stem - also when a tomato plant starts flowering it is in a survival mode to produce fruit to survive - with a new transplant the plant then is using it's resources to produce fruit when in fact it should be producing a better root system and plant foilage to be able to handle the long term flowering and fruit development- so you are ok removing the flowers - now if your plants were determinate don't do so as you get 1 crop that ripens close to all at once - I just let them go on growing -
I fertilize organically (Dr Earth tomato and veggie fertilizer 1 cup) at transplant and when fruiting - only twice - some people only use fish emulsion and kelp liquid (I use this on seedlings)- it depends on your planting medium as some people buy those that are pre fertilized (not me)- there are several goods ferilizers out thee just get well balanced one
when you say you bought the plants I assume in 3-4" pots and are just now transplanting into 40cm pots - how many gallons are these pots - I wonder why you are just now transplanting? were the plants not hardened off? did you keep them in the small 3-4 inch nursery pots for the 2 months - if so I am surprised they are not root bound

Hi there:

airbrush - I'm using premium potting mix in a 40cm pot...um, I'm not sure how this converts into gallons...

mtbigfigh - I think I might have left it a bit late to transplant them now - they were very little plants when i first bought them (around 2 inches), then they just started growing taller and taller! i was told originally by the nursey owner to let them get to around 5-6 inches before I transplanted them into pots. But I realised later when I saw the flowers that I might have left it a little late!

So from what you've both told me, you'd recommend pinching off the flowers now so my transplanted plants can grow stronger and larger, and that this will be better for them in the long run. I will do as you advise; I guess I'm just terrified the flowers will never grow back! :)

lily, if your pot is 40cm tall as well it's around 14gal. I see your from down under. You will have to water at least twice a day due to the heat. I grow mostly in containers and us BioBizz BioGrow which I found to be an excellant product and the tomatoes thrive on it. I'm sure you can get it where you are, just google it. Use it as directed twice a week and you should be good to go.
The other thing you need to do is provide support for your plants. Either erect a cage around your plants or put a stick in you pot and tie the main stem to it periodically as it grows because when you start getting fruit it will get heavy. The other thing you will have to decide is if you want to remove the "Suckers" that develop between the lateral branches and main stem that turn into more branches as well. If the plants are going to be in direct sunlight for most of the day you may want to let them grow to provide more shade for the plant. Don't worry about the flowers as they will return. Ami

Hi Ami :) Yes I'm from down under; and I was getting quite concerned about the heat! Today was 32 degrees and it hasn't rained for over a fortnight...

Speaking of watering; are you supposed to water until liquid runs out the bottom of the pot, which takes around 5-6 litres? I don't think my container's 40cm tall, it's just diameter; the pot itself is a little bit wider than it's tall. I have a picture:

Are those lower branches 'suckers' I'm meant to pull off?

Here is a link that might be useful:

lily, heres a link on pruning tomato plants. 4-5 liters per plant sounds about right. What you want to avoid is the plants not getting enough water where they start to wilt which stresses the plants and can cause other problems. From the picture your plants look pretty good. Ami

Here is a link that might be useful: Pruning Tomaoes

Thanks very much for the link Ami :)Do you live down-under too?

One more quick qu about fertilising; how often do people fertilize their tomatoes - I have one plant currently growing fruit (didn't pinch the flowers off fast enough) - are you meant to fertilize more often in that case?

lily, I'm an American living and working in Germany. Fertilizing plants in containers requires more frequent applications than growing in the earth. It also depends on the type of fertilizer you use. The BioBizz BioGrow I use is an organic Fertilizer and you can use it 2 or 3 times a week with no problem. Normally the larger the plant the greater the nutrient uptake and more frequently you need to make your fertilizer applications (When growing in open containers as you are). Earthbox or SWC's (Self Watering Containers) is a different story. Ami