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4 Reasons Your Tomatoes Are Not Ripening + How You Can Help

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Tomatoes not ripening? Here are the four main reasons why your tomatoes aren't turning red, and what you can do (if anything) to help ripen your tomatoes.

Unripe tomatoes on vine

Why do tomatoes turn red?

Tomatoes turn red because of their lycopene content. What is lycopene? From Web MD (emphasis mine):

Lycopene is a naturally occurring chemical that gives fruits and vegetables a red color. It is one of a number of pigments called carotenoids. Lycopene is found in watermelons, pink grapefruits, apricots, and pink guavas. It is found in particularly high amounts in tomatoes and tomato products.

In North America, 85% of dietary lycopene comes from tomato products such as tomato juice or paste. One cup (240 mL) of tomato juice provides about 23 mg of lycopene.

Processing raw tomatoes using heat (in the making of tomato juice, tomato paste or ketchup, for example) actually changes the lycopene in the raw product into a form that is easier for the body to use. The lycopene in supplements is about as easy for the body to use as lycopene found in food.

People take lycopene for preventing heart disease, “hardening of the arteries” (atherosclerosis); and cancer of the prostate, breast, lung, bladder, ovaries, colon, and pancreas. Lycopene is also used for treating human papilloma virus (HPV) infection, which is a major cause of uterine cancer. Some people also use lycopene for cataracts and asthma.

How does it work?

Lycopene is a powerful antioxidant that may help protect cells from damage. This is why there is a lot of research interest in lycopene’s role, if any, in preventing cancer.

Note that our bodies find it easier to use lycopene once it's been heat processed. This is why I let my kids eat plenty of our homemade salsa, spaghetti sauce and ketchup.

So – no lycopene = no red tomatoes.

Reason #1 Your Tomatoes Don't Ripen = Time to Maturity

Each tomato variety has a time to maturity, i.e., days that it takes to ripen fruit from when the seed is planted. As a northern grower, I make sure to include some varieties that have a shorter time to maturity, along with some of the larger, longer season tomatoes.

If we get a particularly bad year, the short season tomatoes may be the only ones to have time for ripening on the vine, but usually they are simply the first tomato plants to give me ripe tomatoes for the season. As the season progresses, more varieties ripen.

Most tomato fruits ripen in six to eight weeks after blossoms pollination.

Some of my favorite short season varieties are:

  • Early Girl (hybrid)
  • Glacier (heirloom)
  • Stupice (heirloom)

Cherry tomatoes also tend to ripen sooner than larger fruited tomatoes.

tomatoes not turning red, not ripening

Reason #2 Your Tomatoes Aren't Turning Red = Temps are Too Cold

We ran into this problem in the summer of 2014. The spring was cold and wet, and the summer was cold and dry.

My friend, Tami, who busts her tail to start her seedlings early in her greenhouse and get them out in the garden as soon as absolutely possible, saw something she never saw before. Instead of getting red, her tomatoes stayed pink – but they rotted as if overripe.

She harvested all the pink, soft tomatoes and made some very ugly tomato salsa, but the flavor just wasn't very good.

As the season progressed, the tomatoes that did ripen were bland and flavorless. I took to picking them as soon as they started showing the first blush of color and bringing them inside to fully ripen, because the nights were so cool. The peppers were the same way. Full size, but they stayed stuck in the mature green stage until I brought them in to the counter, where they turned red in a couple of days.

Tomatoes give off their own ethylene gas to promote ripening, so there's no need to put them in a paper bag with an apple to promote ripening – unless you're really in a hurry.

Reason #3 Your Tomatoes Are Not Ripening = Temps are Too Hot

This year (2015), many area of the country are running into the opposite temperature extreme – it's too hot for the tomatoes to ripen. While tomatoes are generally heat loving plants, roasting heat is a problem. Cornell University Cooperative Extension notes:

The optimum temperature for ripening tomatoes is 70 to 75°F. When temperatures exceed 85 degrees to 90 degrees F, the ripening process slows significantly or even stops. At these temperatures, lycopene and carotene, pigments responsible for giving the fruit their typical orange to red appearance cannot be produced. As a result, the fruit can stay in a mature green phase for quite some time.

What can you do if you're stuck with green tomatoes and intense heat? Once the tomatoes have reached mature size, you can bring them inside to finish ripening. Remember, tomatoes like it 70-75 °F – just like many of us humans.

See Summer Gardens – Dealing with High Temperatures in the Garden for more tips on coping with extreme heat.

Never put your tomatoes in the fridge! Keep them at room temperature. With apologies to my husband's late great Uncle Bill, who worked on the railroad for many years and shipped tomatoes in refer cars – don't store tomatoes in the refrigerator.

Cold temps turns the sugars in the tomatoes to starch, ruining the flavor and making them mealy and bland. This is part of the reason many store tomatoes taste so bland. They are shipped in refrigerated trucks. Tomatoes stop ripening and don't rot, but the flavor is subpar.

Reason #4 Your Tomatoes Aren't Turning Red – They're Not Red Tomatoes

With the growing popularity of heirloom tomatoes, there are many varieties now available that simply do not turn red, even when ripe. Tomatoes varieties may ripen to pink, orange, yellow, purple – even green. If you're trying a new variety of tomatoes, make sure you know what the mature stage is supposed to look like, so you don't miss out on the yumminess.

For instance, when I first tried garden peach tomatoes, I gave a plant to my mom. She didn't tell my stepdad what she was growing. He saw the thin skinned, lightly fuzzy tomatoes in the garden, and thought they were sick. He picked the ripe tomatoes and tossed them out.

Mom went looking for her tomatoes and found them gone. They got it sorted out, but she had to wait a little longer to try the tomatoes.

Since I plant several different colors, I always note which plant is where on my garden charts. I also take care not to place plants that have similar size fruit but mature to orange and red next to each other, so I'm not mistaking underripe red fruit for ripe orange fruit.

How to Tell When Green Varieties of Tomatoes are Ripe

I've been growing Green Zebra tomatoes for a number of years, because the flavor is excellent and they usually produce a good crop here. As the name implies, they ripen green with stripes. As with other green varieties I've tried, you can tell they are ripe because the underlying color of the green tomato turns more yellow/golden instead of white/lighter green when they've reached full maturity. The flesh turns soft and juicy.

Ripe green zebra tomato

2020 Possible Factor – Wildfires?

I've noticed this year that my tomatoes are struggling to ripen even when other conditions are right.

A reader contacted me recently and was talking about shifting sunlight affecting plant growth. (The sun goes through cycles and the lighting shifts over time.)

This got me thinking about how the smoke from wildfires is spreading over large areas of the planet.

Obviously, this does impact the sunlight hitting (or not hitting) the ground. I haven't seen any studies on this yet, but it seems likely this could affect ripening.

One study I did find indicated that increased levels of CO2 can interfere with ripening. They tested higher levels than we would normally see, even with smoke.

If smoke is thick, it can clog the stomata in the leaves of the plants, and interfere with respiration. This could stress the plant and slow down ripening.

I'm curious if anyone else has run into this phenomenon.

When Your Tomatoes Finally Do Get Ripe…Or If They Don't

Check out these recipes that will help you enjoy your harvest year round!

Yes, Green Tomatoes are Safe to Eat!

Also, if your tomatoes refuse to ripen, green fruits are safe to eat. Just process them in some way before eating, such as cooking or pickling. We turned the green tomatoes knocked off our plants during a hail storm into green tomato pickles (recipe here).

Other Reasons For Strange Colored Tomatoes

Sunscald – Light colored, leathery patches, generally found on the top or side of the tomato, may be sunscald. Sunscald is due to intense sun exposure. If not spoiled, the rest of the tomato may be used. Sometimes the scald leads to rot.

Soil Fertility IssuesCornell University Cooperative Extension notes, “high levels of magnesium and low levels of potassium can lead to conditions like blotchy or uneven ripening or yellow shoulder disorder.”

Blossom End Rot – When the blossom end of your tomato fruits has a small or large black lesion, this is blossom end rot. It's linked to low calcium availability in the soil, so adding calcium during planting may be helpful for avoiding it.

BUT – even when there is calcium in the soil, too much or too little rain can make it unavailable to the plants. Regular, even watering is best. Read “7 Steps to Stop Blossom End Rot” for more on the causes of BER and how to prevent and control it. 

For more tips on dealing with excess rain, see Too Much Rain in the Garden – Managing Wet Dirt and Waterlogged Plants.

Extreme case of blossom end rot on tomato

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You may also enjoy more posts from our gardening section, including:

green tomatoes on vine

Originally published in 2015, last updated in 2020.

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111 Comments

  1. Hi Laurie, thanks for a great article. I didn’t know that tomatoes don’t ripen when it’s too hot. We have temperatures into the 90s on Vancouver Island, for the first time that I remember. And our tomatoes are slow to ripen. Now I know why. Do you think shade-cloth would help?

    Thanks also for the excellent tip about not putting them in the fridge.

    More power to your elbow!

    Very best…Pauline

    1. Anything you can do to get the temperature into a better range may be helpful. Each growing setup and microclimate is different, but if it’s not too difficult to arrange it may be worth a try.

    2. Shade cloths definitely help. We use them in Texas every year! A cool “shower” in the evenings after a hot day helps too. We just turn a sprinkler on after the sun is down (if you get a lot of rain, you might not want to do this, but otherwise, the overhead watering allows the plants to cool off after a hot day).

    3. My tomatoes mature to full size and stay hard as a rock? Is it something to do with the soil? It’s the tgird year. I have tried less plants, less water, and they are in a raised bed in perfect sunlight?

      1. Do you always grow the same variety, or different varieties? Different varieties have different textures and perform differently under the same growing conditions.

        Have you done a soil test? Sometimes soil that is low in potassium can lead to uneven ripening/hard spots. Temperature fluctuations and over-fertilization can also cause problems.

  2. I have 2 grape tomatoes plants –one I had out side and it has tomatoes forming on it. The other is about in my green house and is 5ft tall but has noting forming on it, it gets flowers but they dry up –I check to make sure it has water and it does. What is the problem?

    1. High temps will also cause blossoms not to set. My greenhouse tomatoes started setting fruit sooner than the ones in the garden, but once the temps got warmer, they stopped setting fruit because the temps in the greenhouse were too hot. That’s one possibility.

      The greenhouse plant may also lack pollination. No pollination = no fruit.

      1. I heard there is artificial pollination tricks. Do you know about any?
        I have a fan in my greenhouse and shade cloth on top so the heat shouldn’t be a problem.

          1. That was very interesting as i have been using a cotton bud to wipe the flower then going to another and wiping that flower. Just started so waiting for results. I will try the shaking and flicking. Thanks.

            Cheers
            Terry

          2. hi, I found another better way (in my opinion) of polinating tomato plants. that is with the help of a bird feather. I use feather like a brush on tomatoe flowers and then use it to massage on branches and leaves of the plant. feather transfers the polination from flowers to leaves and branches.
            regards faisal

          3. Yup, the finger-flicking method seems to work fine when I do it. I flicked my flowers several times in the last two weeks and most of them are growing tomatoes now. My neighbors probably think I’m weird doing this, but yielding delicious tomatoes is worth the embarrassment.

        1. One way to help with pollination is to gently shake the plants when there is a light breeze on a sunny day when the plants are producing more pollen. It worked great for my single plant growing in a crate.

  3. when you say to bring them into ripen when you have high temps….do you mean bring the entire plant in te house or just pull the big green tomatoes off? Or temps have been 90-100 and I have a bunch of big green tomatoes but they won’t turn red. My kids are dying to start eating them ha!

  4. Do you have any suggestions on how to get rid of blight from your garden, We have been gardening for over 36 years now and last year got blight on our tomatoes loose every tomato plant, this year we knew what to watch for and had a battle with it. Is there some to do to prepare the soil for next year? We don’t want to use chemicals in garden if we don’t have to. If you have any suggestions at all we would appreciate them . Thank you for your time

    1. What sort of blight, and where are you located? In the north (cold climates), late blight should freeze out in most winters.

      Typical recommendations for organic gardeners are cleaning up (and disposing offsite) all plant debris at the end of the season to reduce the number of organisms overwintering.

      Looking deeper, most of the heavy duty organic/biodynamic gardening resources I’m familiar with feel that disease is a sign that something is lacking for the plants to be healthy. Healthy, vigorously growing plants are much more resistant to disease organisms. You can learn more about techniques for boosting soil and tomato health here – https://commonsensehome.com/grow-tomatoes-organically/2/

    2. I can’t comment on blight…but something much worse.
      The neighbors here with me support the nearby nursery. We all got verticillium wilt the same summer from the same tomato plants bought there.
      I struggled for 4 years watching my tomato plants thrive for weeks and then die with awful brown marks from the roots and in the arteries/stems. The wilt destroys the arteries from the root to the stems–the very delivery system that keeps the plant alive.
      The fifth year, I discarded the wood structure in the raised bed, discarded the soil, and bought new soil and used blocks instead of wood.
      I also sprayed ‘Actinovate’ into the new soil(since the old soil was still on the ground, and in the soil cloth on the ground, & the blocks were more than likely contaminated too)and treated the new plants every two weeks.
      My plants are the healthiest, prettiest ever and the tomatoes are beautiful.
      After 4 years of disgust, I have tomatoes.
      Now, I must say I have contaminated soil where I moved plants around the house to grow as many tomatoes as possible against the house.
      These spots killed 2 dwarf lilacs, 2 rose bushes, a butterfly bush, a boxwood, and almost killed a peach ornament before I removed it and it is living now.
      I replaced these with $3 holly plants since they are immune to the wilt.
      Good luck.

      The site may give you my email for further questions if you have any–this was a long process to overcome/conquer.

      1. If you’re still having problems with blight or wilt, use Daconite. It’s a great fungicide that’s safe for edibles. If you’re an organic gardener, you can use copper or been oil spray, however these are for proactive use only. If you know you have blight in the soil, start spraying about a week after you plant. Keep it up for the entire season, EVERY week, and every time it rains!

        You can also burn the blight out of the soil. Burning is allowed in our city, so we pile and burn our dead plants in the garden at the end of the season. This will kill the blight. If you can stand to go without the affected area, stake down regular black trash bags in the soil and leave it for 2-3 months. The heat will kill off the blight.

  5. Hi Laurie;
    One thing I did when my tomatoes weren’t ripening for the third year in a row was to gather a blanket, some candles and my husband and take them out to the middle of the garden. We stripped and made love in the middle of the tomatoes. Good love, enough to make the tomatoes blush.
    it worked! With-in two days they were on their way being ready to pick; they turned faster than any year before once they started. Thing is, i wasn’t doing it for that purpose, but to get over a rough spot in our relationship at the time. Well, the rough spot didn’t end but we had great tomatoes that year.

    1. And one more thing my mom taught me was to put them in a brown paper bag if they wouldn’t turn. She swore by it and that also works.

  6. For the second year in a row, I am discovering that someone has been vandalizing my tomato plants. Last year, my first and experimental gardening year, I grew my tomato plants from seeds. This year, I bought a small caged planter which was ripening some 5-6 cherry tomatoes a day when suddenly no more ripening is occurring. There are some 40 beautiful green tomatoes which are growing in size, but no coloration. There is everything needed in the soil, and ambient temps with plenty of rain and good drainage. Here’s the thing… I live in Memphis on Harbortown@ Mud Island. It is resort style living and is very safe. However, I have come to the conclusion that one or more of the guys on the landscape crew that works for the homeowners association is/are the culprits. I don’t know why, but someone has taken what I guess was a razor or a blade of some sort, and ever so slightly, shaved areas of the branch and stem fuzz. The first time I noticed it last year, it was about mid season and the plants never bore another fruit. This time, it took a few days after their normal Wednesday grass cutting before I noticed it. The shaved areas began turning to the color of hay so it took time to show up. It caused some of the branches to start turning yellow, so I immediately trimmed any yellow leaves and removed the dying branches as I identified them. I used masking tape to save a few flowering stems and that worked because these stems developed small callouses but survived and are now beginning to flower and bear fruit and new leaves. It seems that the lower stems are still thriving and flowering, but the rest of the plant, at the shaved upper portion, though still supporting these beautiful green cherry tomatoes has been affected by the tomato bandit. All I can say is that he must hate me for some reason unbeknownst to me. It is a Hispanic Crew and I have been kind and generous in occasionally offering cold drinks. I realize these guys have had experience with farming and know secrets of raising or discreetly sabotaging plant yields that is par for the course with farming. I have tried to do the research on how to save my plants and jump start their ripening process, but I have found very little info. I usually am around when the landscapers come around, but they arrived and cut very early the last time. I will take my plants in the nite before from now on, but I am thoroughly disgusted! I had to put locks on the gates to my yard so that now they will have to knock on the front door to enter my yard, but I just can’t imagine what I did to make them hate me so… My questions: what can I do to start my tomatoes ripening again and is it safe to move the plant weekly.

    1. I’ve never heard of such a thing. If you know for sure they’re being vandalized, it would be safer to move them then to let them get damaged.

      Unless the tomatoes reach full growth, they won’t ripen.

      I know stems buried in the ground will shoot out new roots, but that’s no so helpful for top of the plant damage. You might try foliar feeding with fish hydrolosate and compost tea or effective microorganisms to boost cell growth, but I’ve never dealt with this situation.

      1. Believe me, it isn’t paranoia. I actually finally caught one of the landscapers in the act, but the evidence doesn’t show up for a couple of days with yellowing of stems affected. The guy laughed it off. I guess it was just a cruel joke to them… To get my tomato plants to ripen, I used water with epsom salt and molasses to feed the plants for a few days. In about a week, they started turning red again.

        1. I used to live in Memphis.. I can understand this happening .. Memphis has a hate vibe .. it’s so weird. Lived a lot of places…
          such a beautiful city, ????

  7. well I picked one of my tomatoes yesterday put in the window it got ripe and had a great taste so I guess when I need a tomato will bring it in the day before

  8. Thank you, I have been worrying about my tomatoes. We’ve 85+ degrees this summer and all my tomatoes are green (first year with a garden) and have been for some time. Our cucumbers, green beans, peppers, and pumpkins have been doing well. Also, we have some tomatoes with blossom rot which I never heard of either so I will have to add some calcium to the soil.

    1. If you think your tomatoes are full size, you might try picking a couple and bringing them inside to ripen. A thick layer of mulch will also help moderate soil temp.

      1. I just started my garden this year in south Florida. I know this may sound like a stupid question, but when can you tell if your tomato is at full size? I have Bonnie original and also Bonnie better bush. I have one tomato the size of a tennis ball, however it is still green. Please advise. Thank you.

        1. Mature tomato size will vary with type and conditions. You can check the packaging or online listing for expected size at maturity to get a rough estimate, but patience and familiarity with a variety are the most reliable ways to know for sure.

          1. Thank you. Picked one about a week ago, put in brown paper bag…and it is still green!!!

          2. hmmm… odds are it hadn’t reached full growth when picked. You could stick an apple in the bag to try and give it some color, or have a fried green tomato.

  9. In past years I’ve grown my tomatoes in two of my flower beds which only catch the morning sun. They always did well. This year I planted in another small garden with intense sun all day. Although the tomatoes are great in size they are not totally ripening on the vine. We’ve been having 90 degree days so apparently that could be the cause for slow ripening. Could the intense sun also be causing sun burn on the tomatoes?

  10. Hi Laurie,this is the first time in 5 yrs that they didn’t turn red and i have been worried, i didn’t plant them my landlord did and i called him today and ask him why they are still green he replied “He don’t know!! well i picked some the other day and cook them and they turned out ok,so i guess they are all right,i didn’t know that the heat would effect them and it has been quite hot here in Omaha Ne,thanks for the info now i wont worry about them anymore at first i thought someone had put something on them,i was afraid to eat them at first,my landlord don’t stay here this is a house with two apts, upstairs and down and i live up, but we have a great big yard and stuff and it quite nice and the garden is in the back yard and on the side of the house and all of them are still green,well again thanks a lot,yours sincerely calm down!!!!!

    1. The weather this year was tough on crops in many areas. You’re not alone! Try bringing some inside that look like they’re reached full growth, and put them with a fruit that gives off ethylene gas like an apple.

      1. Thanks i did try that bag in a dark drawer trick but i didn’t put no other fruit in it and it WORK!!! i took out t tomatoes the other day and they all were red,thanks so much for your help yours truly a believer!!!

          1. i have passed the info to some others i know that was in the same boat and have gotten messages that it worked for them also, again Thanks for all your help!!!

  11. HI, i tried vigorously flicking and shaking my tomatoes but they refuse to pollinate? What am i doing wrong, is there a technique i’m missing? possibly tugging on it lightly?

    1. I wouldn’t tug. Are you familiar with how pollination works? Pollen has to move fro the stamen to the stigma, then down the pistol to the ovule. This transfer can happen within the same flower (self-pollination), or between plants/flowers (cross-pollination). You might try gently brushing those bright little clusters of pollen from one blossom to the next using a small paint brush. Think bees and butterflies, and their little feet passing from flower to flower.

  12. I had two types of tomato disease this summer. First the normal wilt I get in September but it came in June, we had a wet June in NJ then a dry summer. That one always hits my ROMAs. The second one was a black spot that climbed up the stem of the plant, leaving healthy foliage above and brown below. All the tomatoes that I picked then had brown spots that expanded until the fruit burst leaving a brown foul smelling liquid. Anybody know what it is? And what to do?

    1. Glad your tomatoes are doing well. We’ve had an unusually cool season again this year, and mine are struggling to ripen. Last week’s hail storm didn’t do them any favors, either. Hopefully next year will be better!

  13. Hi Laurie. Seeing some of these issues here in our Harrisburg PA garden as well. Our current crop of tomatoes are beautiful but we’ve been picking them green and bringing them indoors to “red up” but our bigger issue is our zucchini. I had 4 plants in the soil and have gotten only 6 zukes. I have done a soil test and came up with “slightly acidic” so I’m wondering if you have a link to deal with soil issues? I would love to improve our soil but don’t know which direction to go. We’ll likely be doing raised beds this coming summer (2018) so maybe we’ll have better luck with new garden soil. Also thinking of adding mushroom soil and some peat moss or sand to lighten up the current garden soil. Any thoughts?

    1. Have you done a full soil test, or only pH? Generally speaking, more organic matter is good for every soil. Unless it’s terribly heavy, I wouldn’t add sand. Even then, I’d go for organics first – compost, rotten manure, etc. The peat moss would make it more acidic, not less, but the mushroom soil should be fine.

      Many county extension offices offer soil testing, and will typically help you develop a plan for improving the soil. There are also inexpensive home test kits that cover Nitrogen, Phosphorus and Potassium. They may not be as accurate as the lab tests, but it’s a starting point.

      Do you have plenty of bees? Are the plants making blossoms, but not setting fruit, or not making blossoms? This post (Tomato Flowers But No Fruit, or No Tomato Flowers – 9 Troubleshooting Tips) focuses on tomatoes, but many of the same tips apply to other garden plants.

      1. Hi Laurie, last things first …. we have plenty of bees, butterflies, etc. so no problem with pollination. The soil test kit is one I bought in our hardware store and I believe it only did the pH … not a full test. I will likely do the mushroom soil this fall and another thing that might be detracting from our success is a tree that my husband allowed to grow on the edge of the garden (maple I think). I notice everything grows so much better about 5-6 feet away from this tree. So I think expanding the garden away from the tree would be beneficial. Thanks for your tips. I may contact Penn State Extension Service to help us with the soil content.

          1. Well, here we are, a year later. Spoke with our nursery guy who suggested moving the garden away from the tree. First … no time to do this, nor is there another available area with desirable sun. Many mature trees on our property too. Second suggestion is to do raised beds. Did so with organic garden soil (purchased) amended with compost and covered soil between plants with straw. Great tomatoes but only red ones are cherries. Big ones stay green … our temps have been high tho. Zucchini (1 plant) great flowers no fruit.

          2. Are you getting female flowers on the zucchini, or just male flowers? The male flowers start up before the females. Did you ever get around to testing your soil to see if any nutrients were lacking? Usually zucchini are pretty forgiving, but it never hurts to check.

  14. We live in Baja, Mexico and have a real problem with our tomatoes. Tomatoes don’t ever seem to ripen properly. Half of the tomatoes’ exteriors will turn red, but the inside remains yellow and quite hard. I’ve tried leaving them on the plants longer, and bringing them in and ripening in the sun on my counter. Nothing seems to work. The taste of the tomato is different too. . . .kind of tart or sour.

    I’ve been growing tomatoes for years and have never had this problem. Any ideas?

    1. I haven’t had the opportunity to grow in that area, but I do know it’s a big commercial area for tomato production.

      The most likely culprits are stress or disease. Defoliation, over or under watering may cause problems. Have you done a soil test? Potassium deficiency may cause a problem called blotchy ripening, which is pretty much what it sounds like. Areas inside and outside the tomato don’t ripen properly.

      Sweet potato whiteflies and silver leaf whiteflies can introduce a toxin to fruits that prevents proper ripening. You can use sticky traps to catch them.

  15. I have big boy tomatoes. They are not turning red. How can I get them to turn red when they are in my garden?

    1. Big Boy Tomatoes should start to ripen about 78 days after transplanting them into the garden, so a little over two and half months. If you haven’t reached that time, be patient. Beyond that, follow the advice in the post.

  16. I am growing Opalka and Box Car Willie in New Baltimore, MI. Have beautiful clusters of big tomatoes but none are turning. I read somewhere to add a 16 oz bottle of 100% pure coconut water in a 2 gallon container when I water. Has 26% potassium, 4% calcium, 4% phosphorus and 8% magnesium. Sounds like a recipe for delicious red tomatoes soon! I will let you know in a couple weeks. Thank you.

  17. superb article. my tomatoes are superb on the vine totally green hanging in bunches ready to ripen.
    however we have had quite an exceptional couple of months with very hot sunshine taking the temperature well over the norm. I am hoping that it is the temp. that is causing all the problems. everything else is perfect.

  18. Hi, thanks for the article! I suspected my bumper crop of tomatoes wasn’t ripening due to a record-breaking cold spring/summer here in South Dakota, but wanted to be sure.

    Here’s a trick for “hot housing” your own tomatoes. Go ahead and pick them when they’re full-size, and put them in a large paper bag with an apple or a banana. These two fruits give off huge amounts of natural ethylene gas and will encourage your tomatoes to ripen. Once your tomatoes have some blush, you can remove the apple/banana or leave them to speed ripening. You’ll sacrifice that fruit, but you’ll have ripe red tomatoes!

  19. I planted organic Roma tomatoes this year. We had a hail storm early in the year that made my poor little plants look like sticks, but I tended to them like babies and they have grown like champions. Now I have a bunch of tomatoes, but they’re not ripening. I’m going to try the paper bag with an apple method, but someone told me they weren’t ripening because I’ve planted jalapeno peppers in the same raised bed. Could the peppers be the cause for the tomatoes not ripening?

    1. I’ve never heard of that, and I’ve had peppers and tomatoes planted right near each other in the past with no issues. Maybe they’re simply running late because of the stress earlier in the season?

    1. I’m not sure what the problem may be. I tried an online search, but didn’t come up with anything that specifically mentioned soft fruit and no other symptoms.

      Has it been very wet in your area? Excess moisture can make fruit soft. Have you grown this variety before? If not, perhaps it’s naturally a softer fruit. That would be odd, but it’s possible.

  20. I have a few questions from this years tomatoes.
    1. I have found a few during this growing season with no seeds inside. Does that mean they were overripe? They tasted fine.

    2. Some this year were very green and slimy around the seeds. They did not smell good. I didn’t eat those. What did that mean?

    Thanks so much for your help and time.

    1. I know that no seeds is not a sign of overipeness. Different varieties of tomatoes have different amount of seeds, and tomatoes will also set more or less seeds under different growing conditions. Some tomatoes are now even being advertised as “seedless”.

      As for the inside issues, research did not turn up much. I suspect some sort of fungal issue promoting spoilage, given the description. Our neighbors had a similar issue this season due to heavy rains during harvest time. They do not trellis their fruit, and much of it was in direct contact with the ground. We trellis our tomatoes, and did not have similar issues, although we still had foliage stress and splitting from the heavy rain.

      You may want to consider trellising, if you don’t use it, and inoculating your garden with bacteria to help crowd out the bad bacteria. There’s more on EM-1 and other helpful bacteria (plant probiotics) in this post – https://commonsensehome.com/organic-fertilizer/

  21. I have big boy and big beef steak tomatoes plants planted. This is my first time. I have both planted in large pots. They’ve been planted for 21 days and have different sizes of tomatoes on them but all are green. Not sure how big they are suppose to get before they are developed or if they are suppose to still be green. I planted the plant not the seeds. should I keep waiting or pick one and bring inside? Please help. Thank you!

    1. Be patient. Both Big Boy and Big Beef Steak produce fairly large tomatoes, so they may have some growing left to do. The estimates to fruiting are just that – estimates. Growing conditions can slow down or speed up ripening.

      When tomatoes are ready to ripen, before they turn red, they will turn a slightly lighter shade of green. Once you’ve seen it, you’ll know what to look for in the future.

  22. Last year in southeast PA was a disaster because of all the rain; it was a little cool also, but the rain rain rain left me with diseased plants and a few mushy tomatoes. This year has been pretty wet also, but not as bad. But it has been hotter than the past several years, and the tomatoes don’t seem to be ripening as well. The big ones just sit, and even the cherry tomatoes we grow, which usually turn a bright red, almost seem more orange or even a little bronze-like this year, and the taste is just not quite as good. So I finally went out on the internet, and came upon your site. Thanks for confirming that the hot weather can slow down ripening. I knew it can slow or even stop fruit set, but your very helpful article seems to confirm what I am seeing about the ripening.
    Location: Southeast PA (Bucks County)
    Varieties: Park’s Nectar, Supremo, Celebrity, Paul Robeson, San Marzano Redorta

    1. We tend to think of tomatoes as heat loving, and they are – to a point. Just like most crops, they have their “sweet spot” when it comes to temperature. They may do okay outside the range, but won’t thrive.

      Thanks for sharing your experience, Mark.

  23. Hi

    Early Girl Tomatoes
    I noticed that two plants had a lighter shade of Green leafs while the other had a darker shade of leaf
    having the same prolem with tomatoes not turning full red.

    inside is white and the outside is light red
    we had a heat wave for two weeks above 90
    I picked all and placed them in a brown bage going to put an apple the apple does not have to be cut ?
    thanks for your help

    1. Tomatoes generate their own ethylene gas, so you don’t really even need the apple. If you want to speed things up, go ahead and use the apple, but don’t cut it open. That will just make the apple and tomatoes more likely to spoil and potentially attract fruit flies.

  24. Where do you find tiger nuts? I have lived in upstate N.Y. for 49 years and I have never seen a tiger here. Do I half to order from Africa?

    1. Thankfully, no tigers, testicles or other nuts are involved in the harvesting of tiger nuts, as they are a root vegetable with a good PR agent. I usually order a bag of Anthony’s tiger nut flour from Amazon (link).

  25. I didn’t read all the posts so someone may have covered it. You can pick green tomatoes and put them in a brown paper bag and into the pantry. Check every day to find those that ripened in the bag.

  26. Thank you so much! Your post really helped me narrow down the reason why we’ve been staring at green tomatoes for a couple of weeks (or more!). It’s been “one hot summa, don’tcha know?” Yes, I’m mixing New England and Midwest dialects. Gosh, I sometimes I really miss the Midwest. I lived in Minnesota for a few years, and worked with more than a few people from Wisconsin. I hope you’re staying healthy and safe.

    1. You’re welcome, and I hope the weather gets a little more cooperative through the rest of the gardening season. We could use some rain here, as most of the recent storms have been tracking north or south of us.

  27. Thank you! I now know the most possible reason why my entire garden isn’t faring well – heat overload! I’ve noticed sunscald on my squashes, tomatoes are staying green, and I know i’ve used a lot of compost in there and watered enough too. Oh, and my squash plants seem to be dying off in August.

  28. End of September 2020 here in Utah and not one of my larger tomatoes has ripened. The cherry tomatoes have, but I’m likely stuck bringing them in to ripen on the counter. I was wondering if the fires had something to do with it because we haven’t had a single clear sky day in probably a month or more.

    1. As I said, I haven’t seen any official studies, but I can see with my own eyes that the sky here is filled with haze, and the tomatoes are so very slow to ripen this year. We’re much farther away (Wisconsin), but I can see the difference.

  29. I am in San Diego, California and it is taking *forever* this summer for my tomatoes to ripen. I grow Purple Cherokee and Japanese Trifele, and this year we are having to deal with heat waves (100+ degree weather for days) as well as wildfires. They are still flowering and setting fruit this late in the season, and overlapping with my Stupice. Let’s see which one will give me mature fruit first.

  30. Thanks for these ideas to think about and apply a remedy to. Here are a couple tricks I’ve found or heard that work, to ripen tomatoes at the end of our short cooler growing season. I water the plants less, about the end of August/first of September. It seems to put the plants under a little stress and encourage them to ripen all at once.

    A friend said she bends the stems over at the bottom of the plant and the tomatoes begin to ripen too, something her seasoned gardening father-in-law taught her. It may be the same idea of less water or a little stress.

    I have also cut off or pulled up very productive stems or plants and hung them upside down in my shed or garage. I can usually get a few more ripe tomatoes throughout the month or tow.

    Lastly, I have learned it’s ok to take the plants out, after trying to extend the season with plastic for a few weeks. Sometimes the prospect of cold rain or cold garden clean up is enough to say it’s time to end even with green tomatoes and look forward to learning and trying another way next Summer. 🙂

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