Not even a cherry.

July 9, 2006 9:18 PM

GardenFilter: Help! Our tomato plants are 6 feet tall and thriving in our NYC garden, but we can't get them to produce a single fruit.

We grew them from seedlings (~2 inches tall) and they've taken to the big planter box where we've put them. No problems there. The issue seems to be that while they don't mind growing up and out, they won't bear fruit. Do we trim them? Cut back stems and stalks as we would a crepe myrtle? How can we get some tomatoes here?

posted by yellowcandy to Home & Garden (19 answers total)

Have they bloomed yet? What variety are they, and when do you expect them to bloom?

When I was growing tomatoes in portland, I didn't get fruit until August. There's short growing seasons up there.
posted by SpecialK at 9:29 PM on July 9, 2006

Are they making flowers at all?
posted by exogenous at 9:29 PM on July 9, 2006

Do you have blossoms?

Failure to set fruit from blossoms is discussed here.

But if your tomatoes are dropping blossoms, I find that inadequate watering in high temperature is the culprit.

If you're not even getting blossoms, then I'm stumped.
posted by i_am_joe's_spleen at 9:30 PM on July 9, 2006

Maybe they're not getting enough direct sun, a common problem in city gardens. Plants get tall and spindly without enough light, so your plants can be tall but not really thriving. Hard to tell without a picture, but maybe they just need more sun. As far as I know, most tomato plants are supposed to be squat and bushy, not tall like yours. But IANATomatoHybridExpert.

Also, are they making flowers? No flowers probably means not enough light. If there are flowers but they aren't developing into fruit, maybe there aren't enough bees around to pollinate the flowers. You can pollinate by hand with a small paintbrush, but you have to make sure you touch the stamens and anthers with the brush - it can be rather fiddly and make you appreciate how efficient bees really are!
posted by Quietgal at 9:38 PM on July 9, 2006

You may be giving them too much water. If you give them a lot of water, they'll just continue to grow more foliage. If you cut back the water the plant will go "oh no! i need to start reproducing!"
posted by Orrorin at 9:51 PM on July 9, 2006

maybe there aren't enough bees around to pollinate the flowers. You can pollinate by hand with a small paintbrush

Umm, tomatoes are usually self-polinating or wind polinated. From here:

TAP YOUR TOMATOES
Tomato gardeners (perhaps the same folks as squash growers) sometimes have plenty of flowers in July but few fruit result from them. Again, pollination is the key.

Tomatoes, in contrast to squash, have perfect flowers. The bloom has both male and female parts inside. For this reason, insects aren’t necessary for pollination. Most times the pollen will naturally drop from the stamen onto the pistil and a baby tomato will result.

Hot or humid weather, though, makes the pollen sticky. It won’t disperse of its own accord. This is easy for a gardener to remedy. Just tap the flower cluster a few times each day with a twig or chopstick. The loosened pollen will then go about its preordained mission.

posted by MonkeySaltedNuts at 9:53 PM on July 9, 2006

Response by poster: OK, good start here, thanks. I'll give you some more info: (1) the plants are producing few flowers; (2) they're not overwatered; (3) they're getting lots of direct sunlight.

I'm starting to think overwatering might be the issue though. Any more thoughts?
posted by yellowcandy at 9:56 PM on July 9, 2006

I think I agree with Orrorin. Perhaps they are being pampered too much? Ive heard that older varieties of tomatoes need to go through a 'hungry' phase shortly before the flowers are expected, if you want LOTS of flowers followed by lots of fruit.
posted by metaswell at 10:39 PM on July 9, 2006

I've never had issues with overwatering.

What varietal did you plant, and when did you plant them outdoors? Have you checked for aphids or other pests that could be robbing the stems of nutrients? Are there buds for flowers that just haven't bloomed yet?'

It's early July -- most short-season varietals that can be planted in northern climates won't start yielding flowers until late july and fruit in late august, unless you planted a Northwest varietal from the OSU labs. If you planted a common varietal meant for a longer growing season, if I remember correctly you might not see fruit until September if you planted in April. It's been a looong time since I grew anything but short-season Oregon tomatoes, though.
posted by SpecialK at 10:42 PM on July 9, 2006

How do you water? A little bit every day, or a good soaking once a week? Tomatos like the later. Really give them a good soaking once a week or so.

Phosphate (potash). Tomatos love it. Give it a go - in the granular form. If you're giving them a high-nitrogen fertilizer, cut that back a bit as well.

And, as others have said, sometimes plants need to be "starved" a bit before they go into reproduction mode.
posted by Jimbob at 11:14 PM on July 9, 2006

My folks grew tomatoes for years. The only other thing I have to contribute is to make sure to clip the "suckers." Suckers are branches that do not produce fruit. You find them in one place reliably. You will see them start to grow immediately next to (less than a mm away) a larger branch coming off the main stalk. They usually grow on the top side of the branch. Just pinch them off when you see them start to grow. IANATomatoeExpertEither, but this is what we've always done. Good luck.
posted by tdreyer1 at 1:25 AM on July 10, 2006

Couple of comments - yay for phosphate and potassium rich fertiliers. When you buy fertiliser, there will be an NPK rating - that's Nitrogen, Phospophorus and Potassium (Latin Kalium, hence the chemical symbol K). You wanna for for ones that are at least equal parts, lest you over-promote leaf growth (stimulated most by N).

tdreyer is referring to what I know as "pinching out laterals", which is nipping off the little shoots that grow in the "armpit" between the main stalk and another shoot. Not every variety needs this, and some gardeners think that you can get a great crop if you just stake up the laterals and feed feed feed (I'm one of them).

I have no further advice, because this is a problem that's rarely happened to me. I do live somewhere climatically very different, growing tomatoes in the garden, and I reckon you should try to locate some gardeners in your vicinity. Local knowledge counts for a lot with vegetables.

If they are producing some flowers but not a lot that says too much nitrogen to me.
posted by i_am_joe's_spleen at 2:13 AM on July 10, 2006

Seconding too much nitrogen. The whole nightshade family (tomatoes, potatoes, peppers) respond to nitrogen by growing loads and loads of leaves and not much else.

Starve the bastards until they start giving you flowers, then feed them something high in potassium, moderate in phosphporus and low in nitrogen.
posted by flabdablet at 4:27 AM on July 10, 2006

I second tdreyer1's advice to pinch out the excess growth, to try and make the plant short and bushy, so it can concentrate on flowering not growing.
My second bit of advice is just to relax and wait. My first round of tom's have been fruiting for almost a month (London, UK grown outdoors), but plants that went in later will begin fruiting much later. I usually have new tom's all the way through September and beyond.
posted by roofus at 5:17 AM on July 10, 2006

When frost catches you with green tomatoes, bring them in and wrap them newspapers, and store in the basement (if you have one, or equivalent, which means probably fridge in an apartment). You unwrap a couple and set on the windowsill and let them ripen, and Voila! Fresh tomatoes.
posted by unrepentanthippie at 5:48 AM on July 10, 2006

It sounds to me, based on almost no evidence, like you ahven't been pruning the suckers, which leads to late fruit set as the plants concentrate on growing foliage. Try googling pruning tomatoes and it'll tell you all you need to know.
posted by OmieWise at 6:01 AM on July 10, 2006

Here's another vote on pruning the suckers. Once you learn how to remove them, you'll get a much better crop of tomatoes.
posted by fcain at 9:31 AM on July 10, 2006

Another vote for more potassium. You might check with your local *ahem* hydroponics store for some bloom oriented fertilizer. I hear Fox Farm's "Big Bloom" is a good organic fertilizer for this purpose. You could also try some bat guano "tea".
posted by kableh at 10:14 AM on July 10, 2006

They may be getting too much nitrogen. Nitrogen causes plants to grow more foliage than flowers.
posted by kc0dxh at 10:25 AM on July 10, 2006