Temps above 85F can retard fruit set. Overcast and wet can also hurt.

Just go out there when the temps are below 85F (perhaps in the morning after the dew is gone) and gently shake the blooms. The idea is to make the pollen come loose and find the right place inside the bloom. Damp pollen will not be viable.

If your plants are "cooking" in the heat, then you might try to get some shade over them to reduce the effective temp. This might help with pollination.

Ted

I water either daily or every other day depending on how hot and dry it was that day (we're in Texas). They're in the sun, some in containers and some in the ground. I use Miracle Gro fertilizer in the water once weekly.

Then as was discussed in the other thread you referenced - quit over-feeding and over-watering them. Cut way back on both. Mulch, shade if possible, light colored insulated containers, less frequent but deeper watering, minimal fertilizer (if any) until after fruit set and you should be fine.

The Blossom Drop FAQ and all the discussions here on blossom drop and the lack of pollination address all these issues as causes of blossom drop, not just the air temps and humidity.

Honestly - too little water and too little fertilizer is much less stressful on tomato plants than is an excess of either one. We tend to think of fertilizer and water as a fix for problems when in truth it is far too often the cause of the problem in the first place.

Dave

Take end of pinky finger or Q-tip...very gently rub on inside of flowers...continue for every flower on same plant type. Wash finger/get another Q-tip, move on to next variety. =)

Contrary to popular opinion, you cannot get tomatoes to polinate and set fruit by transferring pollen with your finger, a Qtip or anything else. very often, especially with Heirlooms, blossom drop at the beginning of the season is very common. Just stick with it and fruit will set. I agree with digdirt, however, that you are fertilizing way too much. And, probably watering way too much. This would cause foliage growth and no fruit setting. Fertilize every two or three weeks with Miracle Gro, its as good as any. But remember, they are in the business of selling fertilizer so of course the will tell you to fertilize more often. Do that, and you'll set fruit.

I don't want to stir up a hornets nest but I would politely disagree that Miracle Grow "is as good as any". I think the chemical fertilizers are quite a bit less effective as the organic fertilizers. There is a lot of chemistry behind it and I woun't go into it right here but all fertilizers are not created equal.

For fruit set try using one tablespoon of Epsom Salt in a gallon of water when you water. Your current fertilizer has way way way too much nitrogen in it. That is why you are getting lots of nice green growth but no flowers. You need phosphorus for fruit set and development, not nitrogen. A good fertilzer (say 5-10-10) would be better at this time. A low nitrogen (the first of the three numbers) is what you are looking for. If your soil is good then there is already enough N in the soil to take care of all the plant growth.

Also, I assume your nighttime temps are above 55*. Tomato plants will polinate just fine in temps up to 90*. Since the blossom has both male and female parts it does help to walk out and shake the plant up a bit to help move the polen arond and get it to where it needs to be.

Get away from the high nitrogen fertilizer. Get away from the blue stuff altogether. Mulch you garden to help the soil retain moisture and help keep the soil temp moderated. Tomato roots love soil that is cool and damp (not dry or doggy) If you want to promote fruit set then stress the plant just a little bit. If it thinks the environment is turning a bit hostile it will do what it needs to do to start making the next getneration, ie fruit set. But fruitset requires the other two parts of the fertilizer formula. If you use a good organic fertilizer when you plant and then a couple of more times during the season that is all you need. I hope you are mulching your garden. Zone 8 locals can get very hot and dry this time of year. One additional thing mulch does: it provides a nice material for the microbes to munch on and produce lots of CO2, something the plants like. The Microbes don't steal N away from the plants and they give off CO2. What a great symbiotic relationship.

I know that when you wrote this thread it was May 22. At that time here in SoCal we were having the typical June Gloom. Overcast days, cool nights. I had lots of good growth and few flowers. But since the weather turned warn and sunny in June everything changed. Tomatoes are setting fruit like firecrackers. I must have 40 confirmed tomatoes on just two Big Boy plants. My peppers have exploded and I am looking at a trmendous crop coming very soon. I said in another post, tomatoes are setting so fast it seems like popcorn.

If you get a better understanding on the science of soil you will switch to the organic fertilizers which help feed the microbial life in the soil which, in turn, will be so much more beneifcial to all the plants you want to grow.

I guess the best thing I could say is to put the horse ahead of the cart and start feeding the soil and not the plants. If you feed the soil you will automatically be feeding your plants. By using the chemical fertilizers you are totally neglecting microbial life that is so crucial to healthy soil and your plants. After all, why is compost so beneficial to plants? It is all the microbial matter that is in compost. Don't kill it by neglect or stringent chemical fertilizers.

Just my two cents worth.

Tom

I was in Austin past two weeks. There was only one day out of the entire two weeks where temps woulda been low enough (92 - 95 that afternoon) for pollen to be viable and it rained that day so it was probably clumped up and immobile in the anther tubes. The rest of the days were 98 - 105F. And the forecast for this week until is about the same. I was in Dallas over the weekend and it wasn't but maybe a degree or two better.

I don't know where in Texas you garden, but I wouldn't hold out much hope for viable pollen in the weather I saw reported over most of Texas, particularly up in the panhandle and even into Oklahoma. Some varieties can self pollinate even up to 98 or so. Most cannot. And I doubt hand stimulating blossoms is gonna help when the pollen is clumped by humidity or sterilized by the heat.