What do I need to grow tomatoes on a roof top balcony?

[DinDjarin]

I have no knowledge about gardening, one of the reasons we bought a flat. My DD has gone out and bought me tomato seeds (which she thought I could plant and immediately start harvesting!). I have never grown tomatoes, or anything edible, before. What do I need?
Balcony is completely exposed, roof top, no shade either from sun or wind. Or birds - do they also like tomatoes?

We used to put them in one of those zip up plastic greenhouse portable things

If you can afford the outlay, Quadgrow planters are brilliant for small spaces and beginners.

www.greenhousesensation.co.uk/quadgrow-planter.html/

@WandaWonder do you mean something like this? https://www.amazon.com/Best-Choice-Products-27x19x63in-Greenhouse/dp/B01CF2514A
How do you stop it being blown around when it's windy? And would tomato plants have space on a shelf? I thought they grew quite tall.

@Porridgeislife Is that the only pot they will need or do will I need to use a larger pot at some point? That kind of put it in a pot and leave it sounds good!

Manure if you can get hold of it

How long is a piece of string?

It depends on the variety of tomato. You can get tiny tomato plants that grow no bigger than 6 inches, trailing tomatoes you can grow in a hanging basket or window box, or huge tomatoes that grow massive, tomatoes that crop all season or ones that all ripen at the same time. And, of course, there are all different types of tomatoes for different culinary uses...

They all need lots of sun though (at least 6 hours a day) so the first thing to do is identify the sunniest spots on your balcony and how much space you have in those places.

Based on my experience, I would go for small, bushy determinate varieties or the small trailing types - then you don't have to worry about them snapping in the wind, blowing over all the time and taking over all your outdoor space. They also don't need pruning like the indeterminate varieties. The trailing types are particularly good for balconies as you can grow them in hanging baskets or on window sills so they aren't taking up floor space or blocking light from the window (because they grow down), you also don't need to worry about getting your eye poked out by a cane... Maybe pick a few varieties that crop at different times. IME 2/3 small tomato plants per person that crop at different times will give you enough tomatoes for summer salads, unless you want loads for making sauces or snacking every day? I would also pick a disease resistant variety, there is nothing more heartbreaking than tending to them all summer only to have them get tomato blight.

It's too early to plant tomato seeds. You will need to wait until the end of March if you aren't growing them in a greenhouse so you have time to do some research.

If you pick a flavoursome variety, feed them and don't overwater them and it doesn't rain all summer, the taste is amazing... so intense, nothing like bland, watery supermarket tomatoes. It's really worth the effort for the taste! Ditto homegrown peas and strawberries. Cut and come again salad and herbs are also worth growing for the convenience/cost, although they don't taste much different from supermarket offerings.

I grow Tumbling Toms - a cherry tomato on a tumbling bush which doesn't get blown around and doesn't need staking.

All I use are two large pots with saucers and potting compost
(or two small growbags will do)
Two tomato plants
A bottle of tomorite - tomato fertilizer
Water

I usually have tomatoes up against a sheltered wall from May to November.

@DinDjarin you only need one pot! You need to grow the seedlings in a smaller pot but once you transfer them, all you need to do is fill up the water once every ten days & stake them once they get tall, and thin out the leaves if they’re cordon varieties.

Tomorite is an absolute must!

I third Tomorite BUT make sure you don't buy compost that has plant food already added. Too much food is worse than too little! Also, the optimum ratio of nutrients is different for tomatoes from the bog standard plant food they add.

@chesirecat99 they're Sweetie cherry tomato seeds that she bought me. It doesn't say how big they grow, just that there are 25 plants in the packet. Our balcony has no shade, only full sun.

is it a case of planting them all an a couple will survive to plant in a pot, or will all the seeds grow a plant?

good to know about the specific fertilizer, I had no idea!

They'll love the full sun. Sweetie plants grow quite tall so you might need a trellis or similar to tie them too. And a watering can. 😊

They are indeterminate tomatoes so they will grow quite big. You'll need a 25cm pot for each one and a cane/trellis. They need space to grow though so space them apart, don't put the pots right next to each other. You could grow 2 plants in a single grow bag (basically a big ugly bag of compost that you grow the plant in instead of a pot). You'll also need to prune them to encourage them to put their energy into growing fruit rather than new shoots.

You need to germinate the seeds inside as they need a constant(ish) temperature above 20C to start growing. Although I had some seeds from fallen tomatoes I'd left for the birds germinate outside during the insane heatwave last summer! They somehow managed to start flowering and fruiting in October/November and are still going now. Use a seed tray or very small pot, then you can transplant them to the bigger pot when they are ready to move outside.

There are lots of videos about germinating/pruning indeterminate tomatoes on YouTube if you google. Good luck!

Growbag and bottomless pots. Stick the canes in the pots in a tripod. Make tiny slits in the growbag and plant basil and tagetes as an undercrop.