Big healthy tomato plants, but no tomatoes.

I grow tomatoes every year, I usually get a lot.

But this year, I am hardly getting anything. It is already late August, and I only have a few tiny green tomatoes.

It has been a very hot and dry summer, but I water everyday, and I thought tomatoes liked heat. The plants seem to like it.

Maybe not enough nitrogen? Would more compost help?

What usda cold hardness zone are you in? When do you start your seeds? When do you transplant your seedlings outdoors? Are you organic? What kind of tomato variety? What kind of fertilizer have you been using? Maybe your solution is simple. For one thing you are doing excellent keeping them big and healthy, now let's make them mature earlier. You've already got them flowering and fruiting too. They are just late to the party. Why is the question.

Could be lack of pollinating insects or too dry perhaps. I believe a bit of humidity is needed for the pollen to stick to the stigma, that's why the advice for greenhouse grown tomatoes in the UK is to 'damp down' paths to raise the humidity level.

My tomatoes got a poor set too, but the plants are not very well grown (low pH and poor soil nutrition...)

You probably did everything right but the WEATHER didnt.  

Very lush growth suggests plenty of nitrogen and water to me.  I would hold off adding fertility.  Do you have the same number of flowers as last year?    If you do, then the pollinators might be the issue.  Are you seeing any bumblebees anywhere in your yard?  They are the most effective pollinators for tomatoes.

Yeah heat can stop them setting entirely once temps get consistently high. Plants look brilliant because they're pouring energy into leaves instead of fruit. Had a year like that with my outdoor toms, not much you can do but wait for it to cool slightly and hope the flowers that come after actually stick.

I am in Denver, Colorado, which I think is zone 6.
I usually just use compost, no fertalizer, but my wife insists on using something I cannot mention here.
I have a few different tomato varieties. One type is called "Sun Gold" - little orange tomatoes, very sweet.
I think I planted in May. I usually have tomatoes much earlier.
We have been having some very hot and dry weather. Many days over 100F.
I have loads of flowers, and tons of bees flying around.

Walter,

Tomatoes do not like arid climates with extreme sun. They can not get pollinated when it's too hot, and they will not get ripe either (I was shocked when I learned it).
This year for the first time I managed to have some edible tomatoes as those that I planted from seeds the other years were just nasty and I tried 10 various cultivars. It's because I started with relative large plants from a nursery. Then a month ago they got scorched and rotted instead of getting ripe. They are on irrigation in fertilized soil.
With a borderline climates for a given species, one year may work and another will be a complete failure even if you do everything right.

I'm also in zone 6 but at a  much lower elevation than you.  Down here on the plains we routinely have a time of the summer where it just gets too hot for new to set on. I've been told that the pollen of most tomatoes varieties is sterile at temperatures higher than 85° F.  I usually still get some cherry tomatoes through the summer so I'm surprised your Sun Golds aren't doing anything. It's probably just too darn hot.

Also too much nitrogen tends to do nothing but produce lots of pretty leaves. If you're just using compost it's hard to over fertilize.  Miracle Grow on the other hand could be too much nitrogen if you're doing more than the package directions.

Like others said, too much nitrogen is a common cause.

It might also help to tickle your tomatoes.   About mid day, tap the steak they are tied too.  Although this permie member has an even more successful method, it involves special equipment that might already be in the house (ask first before borrowing this vibration device)
https://permies.com/t/promiscuous-tomatoes#453950

Certainly in the central plains states and likely wider, the long sustained heat spell will be a factor here for tomato production.  Up here in northern Minnesota, we've had sustained heat and drought.  My watering every other day has helped to produce lots of foliage and even lots of blossoms....with initially no fruits.  As others have noted, pollinators were rather scarce during this period, but as night temperatures cooled into the 60s and 70s F, we started to see more bee activity and rather rapid fruit onset.  But we are quite behind schedule that's for sure.

Walter B., were you getting mountain cooling air at night this summer or was it staying pretty toasty through the evening and into the morning?  If you feel that previous summers already would have provided cooling nights, that could be a factor in your current situation.  As an aside, the other thing lacking in our tomatoes this year is the onset of Septoria leaf disease....this usually happens as the fruits start to ripen and we are only now seeing a hint of it whereas in a normal year it would be pretty obvious by now. Also for what it's worth, after planting potatoes somewhat on time at the beginning of May, the plants took off rapidly, flowered about a month early, and then the vines died back a few weeks later without any obvious disease.  All summer garden was getting good water and soil is plenty fertile with well-aged pig/chicken manure.  I'm now left wondering if I should harvest and get them into the root cellar or leave them in the ground until early fall.

So with the tomatoes now just starting to ripen and the crop yield looking potentially decent (assuming no early hard frost) a new problem has arisen:  Rodentia!  Little buggers search out the fruits that have just turned the deepest red and take two or three good bites, then move on to the next one!!  Grrrrr!!!  We've had this as an infrequent and spotty issue before, but they are really hammering us this year.  Setting out some traps tonight, but if anyone has suggestions for botanical (mint/garlic/lavendar?) sprays that would make their dining experience less pleasant, that would be great.  Final thoughts, Walter.....if the temps are starting to cool, keep the plants moderately watered and look for changes towards fruit set and ripening.  It may be too late in the season, but worth taking notes for coming years ahead.  Good luck!

All things being equal, I reckon the weather is the problem too.  We get very hot days (over 38°C) and coupled with hot winds, the pollen dries out before the bees can get to it.  Since the rumour is that tomatoes hate their leaves being watered (what about rain, I wonder) I'm reluctant to give them an overhead spray.  I'm looking into Rouge de Marmande this year to see if a variety that doesn't need a pollinator will do the trick. Frustrating isn't it?

Hand pollinating or shake the plant.

Compost tea and weed tea.

More sun or more shade?

Our plants started getting tomatoes when we moved them where they got more sun.

I would question the seed source and fertility. A couple of years ago I had good tomato plants, started from seed (Johnny's WI 55 organic) but one plant had no tomatoes. The rest of the plants produced well but one did not. It was green and healthy looking like the others but no tomatoes. I expect quite a bit of variability in plants grown from heirloom seed, some better producers than others, that is to be expected. This should also give a bit of nuance to the population, some liking that growing season and some not as well. We have been very warm here this summer, one of the hotter July's I can remember. I did not put out my transplants until June 18 this summer, had my first ripe tomato yesterday, August 25. The seed package says 80 days for this strain of WI 55. I count 69 days for this first tomato. Started late, maybe my best transplants this year, very warm, a lot of biological fertilizer and water and looking to be a very good crop. The WI 55 love to send out low runners in August, I trim them back. I also cut off any new blossoms once I have an adequate fruit set and put the energy into finishing the tomatoes.

Tomatoes here need a lot of fertility to really produce. I use pelletized chicken litter, gypsum, copper, zinc, boron, hard rock phosphate (TBR), potassium sulphate, liquid fish, Soil Biological and compost if I have it. Water deeply and not so often, watch the plants and check the soil for moisture. Mulch early on to hold moisture and keep tomatoes off the ground. Tomatoes want full sun throughout the growing season.

My garden with TLC and lots of water has done well, the row crops in the area are poor due to lack of rainfall. Fargo, ND has had 8.89" to date (June 25), normal is 16.70.



















some liking that growing season and maybe some not.

Doug McEvers wrote:.....Mulch early on to hold moisture and keep tomatoes off the ground. Tomatoes want full sun throughout the growing season.

My garden with TLC and lots of water has done well, the row crops in the area are poor due to lack of rainfall. Fargo, ND has had 8.89" to date (June 25), normal is 16.70.

Yeah...pretty bone dry here south of Moorhead, MN....It must be the clay soil, but soybeans still looking green and relatively healthy, but not for long if rain doesn't arrive.

We've done pretty well with no mulching in our tomatoes but they are all very flat-growing heirloom types that cover the soil well.  After a good watering, they can go for days through this drought and are looking good.  The rodent problem has always been there, but this year is much worse....we may rethink leaving those vines on the ground in the future.  Checking traps this morning revealed that the likely rodent is a standard meadow vole.  The crop looks so good right now, hoping we can stay ahead of the little buggers as the faster ripening days are arriving.

Seems like a lot of information here.

It is finally getting cooler here in Denver. My potatoes hated the hot weather, but I expected that. Now that it's cooling, the potatoes are coming back strong. I just hope there is still time.

I always thought tomatoes liked the hot weather. Maybe not when it's that hot. Maybe they will start growing fruit, now that it's cooling down?

Denver does not have seasons like normal places. Instead of consistent moderate temperatures in fall and springs, you get fast shifts between hot and cold. In October you might have 90F one week, and 30F the next. April is much the same.

If tomatoes do not ripen soon, they may get hit with a snow storm.

Another possible issue: I have a great reluctance to remove "volunteer" plants. In my experience, volunteers are often the strongest plants. This should no surprise, after all, they overcame great odds to be growing at all. But this might be a problem. The volunteer tomato plants may be too close together. The plants are all doing fine, but that could keep them from making fruit? Maybe if the plants are too close together, they are starved for something that helps them make fruit?

More sun or more shade?

A tree has grown in the path of the morning sun. Tomatoes get full sun, but not in the early morning, or later afternoon.

some tomato varieties will not set fruit in high temperatures -- I grow my tomatoes in a high tunnel hoop house and have to select for varieties that will set fruit in heat since not all do. Do you prune your tomato plants? By that I mean pruning off the suckers that grow in the "elbows", often if I don't prune my plants they will spend a lot of energy making tons of vines but not fruiting as well. Tomatoes are a perfect flower so don't necessarily need pollinators but do need a little wind or shaking of the vines to pollinate them. In the hoop house that's another thing I deal with because if I don't have time to go around and shake them all they don't always get the wind they need to pollinate themselves. Best of luck and maybe they will set fruit better once the weather cools down a little as Autumn approaches.

Former Coloradan here! 👋 Sorry to hear about your tomatoes. A couple of things that may help that I noticed here in Montana--when it's dry here, giving the flowers a slight spritz of water with a spray bottle will help them pollinate. Also, as other people recommended, tap the flowers or use your finger and help pollinate the flowers. It's been ridiculously hot here, but my princess mandarin mini loves the shade I have it under. Lots of fruit coming up, if the frost or the chipmunks don't get them.

ETA: I was curious what kind of tomatoes you planted. Up here in Montana there are seed producers that sell seed specific to Montana's climate and altitude. You may want to consider what type will do at Denver's altitude and climate. I believe the seeds I used was from Three Rivers, which specialize in growing plants that have been hardened for Montana over the years. If you could find something like that for Colorado, that would be cool.

ETA (Again!): The seeds I've used are Triple Divide Organics. Sorry about the edit. Brain is still dealing with my knee surgery--and yes, there is a Three Rivers in Montana!

Do you prune your tomato plants?

I do not. I have never had to do so before. I used to get tons of tomatoes. I suppose I could give it a try.

ETA: I was curious what kind of tomatoes you planted.

One of my best plants is a San Marzano. It is a volunteer. It is growing in a grow bag that I used to plant green onions. In the same bag is small Yellow Pear Tomato plant, that has grown a few tomatoes.

I have a big plant growing Currant tomatoes. Last year, I was flooded with these, could hardly pick them all.  This year, I have some green ones, but no ripe tomatoes yet.

I am growing some Sungold tomatoes. These are amazingly sweet. I used to get loads of them. This year, I am just getting a pitiful few, and they do not seem quite as sweet.

I often grow small tomatoes because it is less painful when the squirrels eat them. Squirrels around here love tomatoes, especially be red one.

A quick interjection....  It's only been in the past week that our entire crop.... paste tomato (seed saved so long ago can't recall variety), Yugo, and Russian Persimmon....really started to ripen.  Pretty rare to be in September with green tomatoes, but seems a lot are in this boat.  Now we are processing like crazy for freezer and canning.  This is the typical month for first frosts, so we have tarps at the ready to extend the ripening period.

....and dusting off some green tomato recipes!

John Weiland wrote: A quick interjection.... Pretty rare to be in September with green tomatoes, but seems a lot are in this boat.  

Good point. I thought I was behind on things, but my princess mandarin mini is still blossoming and growing scads of what are now green tomatoes. Maybe that is the OP's problem right now?

Hi @ll!

Since you mentioned that you already have lots of flowers and plenty of bees around, I suspect the heat is the main issue rather than a shortage of pollinators. Colorado State University actually says that if daytime temperatures reach around 90°F by 10 a.m., tomato blossoms opening that morning may abort. With the 100°F days you've been having in Denver, that seems to fit pretty well.

Here in Spain, when tomatoes are grown under that kind of heat and intense solar radiation, shade netting is very commonly used. Tomatoes need plenty of light, of course, but they do not benefit from being blasted by direct sun all day when temperatures are extreme. Some shade during the hottest part of the day can reduce stress, flower drop and sunscald without depriving the plants of the light they need.

For the tomatoes themselves, I would probably try around 30% shade cloth during the hottest period, especially for afternoon sun.

I would also pay close attention to irrigation. Tomato plants can be surprisingly sensitive both to drought stress and to excess water. Keeping the root zone reasonably even in moisture is usually much better than alternating between very dry and very wet conditions.

I would avoid watering over the foliage if possible and irrigate at soil level instead. Tomatoes are quite prone to fungal diseases, and repeatedly wetting the leaves — especially if they stay wet for hours — can make disease problems much easier to develop.

For future years, though, I still think it is worth planting nectar and pollen plants around the tomatoes to maintain a permanent population of pollinators and beneficial insects. Things like dill, coriander, yarrow, alyssum and other flowering plants adapted to your area could work well.

You could even let an artichoke go all the way to flower — the flowers are spectacular and very attractive to insects — although in your climate I would see that more as part of the garden ecosystem than as a solution to this particular tomato problem.

And giving the flowering trusses a gentle shake now and then may also help release the pollen.

Once temperatures fall, I would expect fruit set to improve quite quickly.