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yumtomatoes

Help with Tomato Seed Germination Dates

yumtomatoes
12 years ago

I want to make sure I understand how to time the germination of my tomato seeds. Most seed companies tell you how to time in terms of last freeze date, which of course where I live is inapplicable. More important here it seems is to time according to night time temperatures so that you can get fruit set before it gets too cold or too hot.

As I understand it from reading on the Tomatoes forum, it takes about 2 months from starting your seeds to get seedlings ready to transplant into containers. Then it takes however long the date to maturity is for that variety. So you add 2 months to the date to maturity (DTM) to know when you should have fruit to harvest.

For instance, my Brandywines have a DTM of about 3 months. So I need to start my seeds 5 months ahead of when I want to harvest fruit.

But I know that tomatoes don't set fruit if nighttime temps are below 55 or above 75. Unfortunately, these last 2 or 3 years we have had nighttime temps in December that dropped below 55 for several days in a row to over a week with only a few days inbetween before the nighttime temps dropped back under 55 for several days in a row. And we had nighttime temps above 75 through at least mid-October - it was just awful.

So that leaves me with November and early December for fruit set. How long does it take from transplant into final containers until you get blossoms? I know it varies by variety, but about how long on average for mid to late season tomatoes? If I get the plants into their final containers by mid-October, will that be enough time for them to blossom and set fruit before it gets too cold in mid-December?

Also, what happened last year was that I did get some fruit set in November and early December only for the fruit to sit there green and not ripen for what seemed like months due to the unseasonably cold weather in January and February. That is not desirable either since the plants require so much care to prevent fungal infections and to maintain consistent watering. I have the additional problem that where I can grow them requires me to move them throughout the day so that they get enough sun due to buildings obstructing the light. Not to mention how often we got close to freezing the last 2 or 3 years and I had to cover them and then uncover them each day. Only to have the next night drop close to freezing again. I think it did drop below freezing for a short period of time at least 1 or 2 nights. So you see, it takes a ton of effort for me to grow tomatoes and I only have space for 2 plants so I need to get it right.

I need to time this so that it is not too cold/too hot for fruit set but yet warm enough so that the tomatoes ripen. I started seed August 10th and 11th for my fall crop but I can start them again September 1 if that would be better. And next year I can start in July if that would be better but obviously, it is too late for this year.

What about for spring crops? By April it is too hot and humid here to set fruit and even if you set fruit in March, May is too hot and humid for the plants to survive and fruit gets sunscalded and otherwise has problems ripening even if the plant survives due to the heat affecting the plant.

So if I start seed November 1 and transplant January 1, that would give me 3 months to have fruit at the end of March beginning of April. Does that sound about right?

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