Gigantomo advice - how to grow big tomatoes

Mine's bigger than yours. Is there something in our DNA that makes humans want to make things really, really big? It's a spirit that's thriving in the City of London, with proposals recently announced for a new building only 5m shorter than the Shard. And there'll be plenty of rivalry at Harrogate Autumn Flower Show 18-20th September, when a new class will be judged on Giant Vegetables.

Included in the competition are the National Gigantomo Championships. The prize at stake is pretty big itself, unlike most veggie show rewards - £1000 prize for the heaviest tomato, with £5000 added if it breaks the world record at the time of the show. That record is currently 7lb 12oz (it was a 'Delicious' tomato).

*Rapidly calculates*  That's something in the region of 3.5 bags of sugar in weight - and probably bulkier because a bag of sugar is denser than a tomato.

Blimey.

Now, I was lucky enough to receive five Gigantomo plug plants from Van Meuwen, this year. Told of their giant dimensions, I raised a sceptical eyebrow. "But do they taste any good?" I queried, with what I hoped was a suitably chummy, ho-ho-we-all-know-the-problem-with-this-sort-of-thing tone of voice. The charming young man at the Press Event in February took it on the chin (it was late afternoon. Of course he hadn't been asked this before) and assured me that, actually, they taste very good.

All five are in the Tomato Growing Position - front of house, full sun, south-facing. Growing strongly. But I'll just reassure any competitively minded Gigantomo growers out there that the chances of my getting my mitts on the £6000 (or even £1000) are vanishingly small.

The strain has already made enough of a splash to have been reported in the Mail Online. These plants, the article says, will grow to six feet. Hmm. Not in my buckets, I fear. These have proved totally adequate for tomatoes up to now, but I sense disappointment in their current residents. The plants wilt with alarming rapidity, even after a darn good soaking the evening before. A watering twice a day seems to be what they're demanding.

How to Grow Big Tomatoes

However, for anyone who is more optimistic than I, Van Meuwen have sent out helpful instructions on how to grow the biggest tomatoes. It would apply to all tomato plants, pretty much. Bob Flowerdew said on BBC Radio Four's Gardeners' Question Time recently that the weight of fruit (on an apple tree, in his instance) will remain constant, whether you thin down the fruit or not, meaning that the more ruthless you are with thinning, the larger the fruit you'll grow. It only remains to ask yourself, How big do I want my tomatoes?

The megablooms seem to come on an extra thick stalk

That aside, this is what needs doing:

1. Understand megablooms. It's a blossom that's got more flower petals than the others because it's made up of two or more blossoms. This is the tomato that will grow and grow, because it's actually two or more tomatoes fused together. (Every Gigantomo truss seems to have a megabloom. On mine, it seems to start off on a twisted stalk that gradually uncurls. You should keep only four trusses on each plant.
2. Allow only four trusses per plant.
3. Thin these down to one tomato per truss (obviously, with Gigantamo this should be the megabloom tomato, but I've noticed that this has happened naturally on a lot of the trusses. Quite a few blooms have aborted, leaving one tomato to grow.)
4. Apply a mulch of manure up to four inches deep, if grown in soil, or as much as possible around the top of the container.
5. Stake strongly. It's also suggested that you cage the plants with chicken wire. (I prefer that green-coated wire fencing that Americans call "dog-wire". It allows the tomato leaves to poke out through the large rectangular holes. Even so, one of the cages has already toppled over and I've had to tie it to the wall behind.)
6. Support individual fruit with an old stocking, or anything that creates a little hammock for it.
7. Give them constant moisture to avoid blossom end rot (oh, dear).
8. Feed weekly - and foliar feed twice weekly with seaweed solution. (Gigantomo not only drink like topers, but eat like gluttons.)

All this should give you something to attract the judges' attention at any veggie show.

Gigantomo tomato plant, caged in as an alternative to staki

As I say, unless something very surprising happens over the next few weeks, my tomatoes will be no threat to anyone. My aim is to grow larger than average tomatoes and hope they taste good. However, if your eye is glinting at the goal of riches, here's what to do if your Gigantomo looks like a winner:

Picking a Show-Winning Giant Tomato

Measure your potential prize-winner until it stops swelling and then pick it when still pinkish, unless the competition is imminent. If it ripens far too early, pick and keep in the fridge for up to three weeks at 8-10 C.

Good luck!

For a follow-up on the competition and what I thought of my crop, see my later post Gigantomo tomatoes taste update.