Q: Why are my tomatoe plant flowers falling off?

[Otto Pylot]

Most perplexing. For years we have always had no problem growing really nice tomatoes. Two years ago we changed the physical location of our garden to accommodate new landscaping. The vegetable garden did just fine in it's new location except for the tomatoe plants. They grew fine but just as the flowers started to open, they would fall off. We saw no indication of any insects. Someone suggested that we had a virus in the ground so we pulled up the plants, turned the ground, and then covered it up with black tarp for the entire summer season. The idea was to "naturally" sterilize the ground. This season, we dug out the area in two circles, removed the soil and mixed in fresh planter mix with other garden soil, and the enclosed the circular area with bender board. Each circle was planted with healthy (assumingly so) starter plants. They are growing quite nicely but as soon as the flowers start to open, they fall off. Ideas and suggestions would be most appreciated. Thanks.

[Jim Carter]

This is something that happens if tomato plants are subjected to too much heat, I think the temperature is above 95ºF.

[Penelope Periwinkle]

don't say where you are, but around here in South Carolina, the temperatures have fluctuated quite a bit this spring. I'm surprised any of the tomatoes have set fruit at all.

Penelope

[Steve Calvin]

What growing zone are you in? Have you had a soil analysis? Have you fertilized with anything?

Way to many unanswered questions to make a call. Bottom line is that your plants don't "think" that they are healthy/mature enough to sustain fruit. Why? Don't know. Too many questions that are unknowns at this point.

[Otto Pylot]

San Jose CA. We planted a week after our rains had finally stopped.

[Otto Pylot]

San Jose, CA. No, we have not had a soil analysis. No fertilizer as of yet. Just fresh planter mix from our local nursery mixed in with some soil from the garden.

[Steve Calvin]

Barring soil problems then I'd "guess" that your plants just aren't mature enough to support fruit yet. They know when they are.

I put composted cow sh*t in every year and 'till it into the soil. That seems to help a lot. But still, if it's too early, the flowers drop.

[Sue]

I'm over here in Los Banos and my tomatoes have suffered from blossom drop for the last 3 years. I have no idea why. Some say the heat but they grow commercial tomatoes around here and my first year of growing them was just great. There seem to be a goodly number of possible reasons. Anyway, this year I've moved my tomatoes - about 8 blocks from here to my gentleman friend's back yard. They are just starting to blossom so it's too early to tell what's going to happen. Sue

[Jim Carter]

I am on the side of those who blame heat. Some of the plant hardiness zones here in Canada have been changed to reflect global warming (the last frost date has been moved forward by a week locally--near Ottawa).

You might try to buy a plant or two that are normally grown in the deep south and see if these plants are able to set fruit. Different types of tomatoes are able to tolerate more heat than others. How are your neighbours' tomatoes?

As an aside...

I have a friend who lives in Kenya (right on the equator). There is only one type of tomato that will grow in the country and that only at high altitude.

The tomato growing season has already passed for those who live in Florida.

[Jim Carter]

I would go with a date later than May 6. May 6 is AVERAGE date of last frost. The farmers in my area are planting as early May

17, where May 24 used to be the accepted date. Department of Agriculture points their finger at global warming. I looked up their address a couple of years ago and they seemed pleased to answer a question from a mere gardener, they even changed their web site as a result of my question! -- Gardening Zones Canada Zone 5a United States Zone 3a

[Jim Carter]

Ah, Hogtown. I am near the real hot air in Ottawa (Perth).

We had a prolonged period when daily temperatures were around

30ºC and my tomatoes were okay. Do you recall the temperature there. -- Gardening Zones Canada Zone 5a United States Zone 3a

[Sue]

I assume that anyone I know that grows tomatoes grows the same varieties that I do, but we've never compared notes. The thing is that one would think that the tomatoes wouldn't be for sale around here if they aren't going to grow around here. Of course, Wal*Mart may not care. I have pretty good luck with the Sweet 100s but what I like to do is can which requires a lot of the medium or large sized fruit. My first year I was able to do this. I'm growing the same varieties - Beefsteak and Celebrity as well as the 100s. I don't have a lot of space so only have 8 plants. I'm just hoping that things work out better this year but I sure do have bug problems I've not had before. Will save that for a separate thread. Sue