16,949 Garden Web Discussions | Growing Tomatoes

Just a few thoughts on the original question of tomatoes setting fruit at low temps. There is a variety, Earlinorth, that sets fruit down to 40 degrees. If you do some serious digging, you can find several Russian varieties that have significant cold tolerance. Also, there are several varieties available in the U.S. that are modestly cold tolerant in terms of setting fruit.
I am doing some work with tomatoes to identify genes that contribute to extreme cold tolerance. I currently have 200 plants in my garden for evaluation. This includes Earlinorth, PI120256, numerous U.S. cultivars, and several Russian varieties. So far, I have seen 3 distinct traits involved in cold tolerance. One is the ability to set fruit at low temps, another is improved root efficiency, and a third is leaf tolerance to cold temps. Each trait appears to be affected by different genes.
DarJones

Very interesting fusion_power - We have done limited research on these Russian varieties but opted to figure out ways to inexpensively as possible heat the GH to min temps - and/or start the seeds a little later next year. It seemed with what we read - the more tolerant to cold varieties came at a sacrifice - mainly fruit size and possibly flavor?
You are more knowledgeable and may know of varieties that offer both fruit set in cold temps and good fruit size/flavor? Regardless - your work identifying genes should result in improved hybrids in the future - for setting fruit in cold temperatures? It seems expanding the low and high range for setting fruit in tomatoes would help gardeners everywhere.
Is the main purpose of your research to improve the temperatures for setting fruit?

Link below is to the FAQ here on 'blossom drop' and should answer your questions I think.
You don't indicate your location or your garden zone in your post so there is no way to know what weather factors may be contributing to your problems without that info.
In generalpollination rates vary greatly from one variety to another so comparing them can be very misleading. And seldom is there 100% pollination on any variety. And if your soil has normal levels of nutrients then excess N probably isn't a factor. Indeed it may be low.
Excess phosphorous may be a factor but no way to know without a soil test.. That leaves heat and humidity as the primary causes of problems IF your pollination rates are sub-par.
Hope this helps.
Dave
Here is a link that might be useful: Blossom Drop FAQ

Thanks Dave, that does help. If you look at the rate of the Sungold (reversed from the OP) it is nearly every tomato on bunches of 6-10 but the fact that the Sweet 100 is producing strings of 15-20 blossoms means that it is not pollinating any less tomatoes only less percent of its blossoms. And I see why Roma is such a popular variety in agriculture, mine has 100% pollination on 5 bunches which i have never seen any tomato do.
All in all I am not too concerned, but I might do a soil test out of curiosity. It is my first raised bed and I didn't exactly measure anything in the mix.
I am in central CA, zone 9b. Had a good mix of cooler days, rain, and only a few hot ones not breaking 95. Not much humidity. Great year so far, my Sweet 100 and Sungold are hitting the 6 foot mark already which is scaring me.
Thanks for the help
Phil

If it said "developed by..." that is a pretty good clue that it is a hybrid.
And yes, seeds for F1 "Window Box Roma" are available from several suppliers so it's not new stuff.
GROWE is a non-profit foundation dedicated to teaching children about gardening and eating properly so I would assume that its name on the label means the sales were part of a fund-raiser.
Dave

In the one experience I had with a stem borer, the stem above the hole remained very small in diameter and growth had slowed to almost nothing; that stem never recovered. I only saw one hole (neatly round), no frass, and when I removed the stem some weeks after noticing the problem, there was no worm in the tunnel; the tunnel was a few inches long and was above the hole.
Perhaps mine was a different sort of caterpillar than yours.


Carol is right people forget the name, and rename crating more varieties which are really the same . Another thing people do is grow abunch of toms and they harvest toms 5 days before the DTM so they think they have improved the original Tom ,so they rename it ,Some are just vain and dont get enough attention and rename a variety in their name or a friends or loved one name. Some get seeds from another country or region and do the same.

Cherokee Purple is the original variety named by Craig LeHoullier, seeds from John Green in TN.
Craig discovered fruits on a plant that were much darker than Cherokee Purple, which has a clear epidermis, and what he called Cherokee Chocolate seems to have a yellow epidermis.
So the two are exactly the same except one is darker than the other,
Below I've linked to Tania's page for this variety where opinions are given, pictures are shown and seed availability is indicated.
And yes, I've grown Cherokee Chocolate.
Carolyn
Here is a link that might be useful: Cherokee Chocolate


Just looked at the weather online, severe weather (hail, tornados) in OK and surrounding area this weekend, moving east into MN (and WI?) next week. I'd hold off, see what they're predicting for your area in a few days. I may not even be able to harden mine off this coming week and plant next weekend as planned
Here is a link that might be useful: Severe weather coming

I am doing this for the first time as well. So far so good, but the mettle is always tested in Aug/Sept when growth skyrockets. My husband installed two others like this. I still have to transplant a few more. Keep in mind tomatoes still need to spread roots underground even though above ground it looks like there is pace for more plants


The string trellis works really well in Florida. Our summer humidity is coupled with daily afternoon showers, which makes for a less than ideal environment. Being able to spread things out allows for much better airflow. Also it makes pruning and harvesting really easy. This trellis is about 6.5 feet tall and I will either pinch off the plants once they reach the top, or just let the branches spill over towards the end of the season.


I checked two sites which usually give heights:
V = the big French database Ventmarin.
http://ventmarin.free.fr/passion_tomates/passion_tomate.htm
CF = the Cultivar Finder at the forum we can't link to or name.
Black Plum:
V = 5'10" - 6'6"
CF = in their 4'-6' category
Italian Paste:
V = no size listed
CF = variety not listed
Blondkopfchen:
V = 4'10" - 5'2"
CF = in both their 4'-6' and 6'-8' categories, which I interpret as perhaps 5'-7'

Thanks for the resources, I hadn't seen those yet.
So it looks like Blondkopfchen, Black Plum, Black Krim, Tula & Cherokee are good ones to try along the fence. I'll try an Italian Paste there too (the seeds were a freebie from TomatoFest, just listed as "Italian Paste", figured I'd try them out).

The amazing thing is that there is not shortage of truss clusters
Hudson, are you saying that you're getting trusses on a stem more often than the usual indet pattern of one-truss-after-three-leaves? If so, that would be an interesting mutation.

Missingtheobvious - I wasn't thinking that at all with the statement - just meant that there were the normal amount of trusses going up the plant. You got me thinking though and I had to check it out this morning. There are the normal - one truss after three leaves.
I did break off the top of one the plants this morning training the stem - dang it - hate it when I do that. There is another sucker close by but it just set the plant back some - I didn't apply more pressure than usual - just hit a weak spot I guess.


I had the same thing happen to one of my two larger plants that I had in a nursery pot waiting to transfer to the ground. It had been outside for a couple of weeks. The first day we go a sustained breeze with some fairly significant gusts, the same 'blisters' appeared. I think it was wind damage. I thought I had given it enough wind protection that day but apparently not. My leaves were a little droopy as well. I brought it back in once I saw it in this state.
It seems to be doing fine now...except for the stem marks.




no but isnt it time to plant out ? they will take off then