growing tomato seeds
It’s my first report on my hybrid tomatoes (see the original post here at hybrid tomato experiment). So how are all the plants doing? Well, there’s good news and bad news — here’s what’s happening.
I planted 8 F2 seeds, and all sprouted — good news so far, especially since they looked pretty good. Too bad it didn’t stay that way! (On the other hand, that’s the reason for experiments — you never know what will happen.)
Of my original 8 seedlings, four have survived. OK, 6 survived, but two of them were growing only so-so. Since I want plants that thrive, I pulled ‘em up and tossed them. Yes, it seems harsh, but I don’t need plants that don’t do well for me.
Hybrid Tomatoes That Survived
Of the four plants that have grown well, two are determinates, one is indeterminate and the other seems almost between the two — like a stocky indeterminate.
One of the determinates, plus the one that’s a definite indeterminate, have flowers — a good sign! So these two are in the running for keeping seeds from the tomatoes they produce. But does that mean that the other two don’t have a chance (except for eating what they produce)?
No, part of this experiment is on how they grow and how soon they produce, but the other part is the actual fruit — how large the tomatoes and even more important — how they taste. There’s really no reason to grow tomatoes that are bland or mushy in texture. So earliness is only part of the reason to grow a variety.
I also live in a very hot and humid place — it’s only April, but it’s been over 90 degrees several times already this season. So any plant that can grow and produce fruit in my location gets an automatic vote for keeping seeds from it.
In my previous post about germinating tomato seeds, I mentioned that I had planted quite a few seeds that were at least 10 years old. While I expected some of these seeds to germinate (I do have some rare seeds in my collection), I wasn’t expecting a high germination rate. At most, I was hoping 25%.
Wow, have I ever been surprised! For some of the varieties, the germination rate has been in the neighborhood of 75%. Brandywine is one of them; Yellow Cherry another. Then there are varieties in the 60% range, like Pineapple and White Bush. Of all the varieties I planted, only Big Rainbow has had a low germination rate. Then again, it might be that it’s been slower and more seedlings will start popping their heads above ground today or tomorrow.
I’m trying to decide if the Terracycle I sprayed on the soil on Sunday helped the germination, or at least hastened it. Sunday hadn’t shown much action with the seeds, but Monday a whole bunch showed up. Tuesday a whole lot more. And even today I see some more new seedlings starting through the soil.
The next batch of seeds, I’ll remember to spray the Terracycle sooner (my fault, my plant sprayer had disappeared and I had to go get a new one…and was a bit slow about it). But now I have a new sprayer.
There’s a Problem, Though…
I have a problem now, but it’s a good one to have. I planted way more seeds than I had needed, because I thought the germination rate would be really low. Yikes! I now have way more tomato plants than I have containers, by a large margin. Time to gift my family and friends with some seedlings, or maybe take them to a farmer’s market to sell, in another month or so (after the second transplant).
So, don’t throw out those old seeds without giving them a try, and keep in mind that they may take somewhat longer to germinate than newer seeds. Remember, when germinating, tomato seeds like warmth and humidity.
I’ll give another update next week on how the seedlings are faring.
Germinating tomato seeds, or more specifically growing tomatoes from seeds, really isn’t that difficult. Using seeds, you can grow a whole lot more varieties than what you find in your local garden shop.
If you’re adventurous, why not try growing a new variety (or varieties) of tomatoes from seeds? Maybe some heirloom tomatoes, while you’re at it?
Tomato Seed Germination Rates
Before I get into the technical aspects of planting, I want to discuss germination rates for tomato seeds. It’s quite rare for all the seeds you plant to germinate, or once germinated, to thrive. While I’m glad when it happens, I don’t expect it. In my experience, 75% to 80% of my seeds in any given packet germinate and thrive. So, I normally plant 25% more than I think I will need of a particular variety. If everything germinates and thrives, I can give away or sell the extras.
A lot of things affect the tomato seed germination rate. For one, how old are the seeds? Whether you buy them online (which is what I do mostly) or pick up the seeds in a garden center, you don’t know how long those tomato seeds have been sitting around. The older the seeds, the lower the germination rate.
(That being said, I have seeds 10 or more years old that still germinate…just slower and with a lower percentage.)
Another issue is how have the seeds been stored? Two things can hurt seeds; too much humidity and…not enough humidity! Too much, and the seeds want to sprout, or else they can mold. Too little and they can dry out and not germinate at all.
How Long Does It Take for Germination?
There isn’t really a set time for tomatoes, as different varieties germinate at different times. The fastest I’ve ever had is 3 days; the slowest 12 days. In general, most germinate in 5 to 7 days. I generally wait 2 weeks before I consider a set of tomato seeds a lost cause for germinating.
Right now, I have SuperSweet 100, Brandywine and White Bush sprouting. SuperSweet 100 raised it’s head after 4 days and at 7 days (which is today), I did the first transplant to a slightly larger container. I had a 75% germination rate with a fairly new packet of seeds. (I planted 4 seeds and 3 germinated.)
White Bush is the next in line, sprouting yesterday (6 days). Brandywine is just starting to poke its head above ground today (7 days). My germination rate is really low with these two, because I am using 10-year-old seeds. (I just did plant some newer Brandywine seeds today for comparison.)
I have about 3 other varieties that haven’t sprouted yet, but once again, these are all 10-year-old seeds. What can I say, I am curious as to how they grow and thrive! Some of my 10-year-old seeds are pretty rare, and I want to try them again.
(Read my update on how well the 10-year old seeds germinated, 10 days out – I was amazed!)
Germinating Tomato Seeds – Tips
First, make sure that you have a nice, warm place for your seeds to germinate. I use a windowsill greenhouse in a south-facing window; some people use the top of their refrigerator. Others use a seed heat mat or a grow light. A soil temperature of around 80 degrees is ideal for tomato seed germination.
The “soil” I’ve had most luck with is a seed starting mix. It’s lighter than a regular potting mix, so it’s easier for the plants to poke their heads above ground. The soil needs to be moist but not wet.
I tend to plant my seeds rather shallow, 1/4 inch or less. Keep the humidity high while you’re waiting for the seeds to germinate. This is where I like the mini greenhouses (windowsill and table-top, because they have a cover that keeps the seeds and soil nice and moist. Not to mention they take up very little space.
I have used jiffy pots and compressed peat disks, with fairly good results. The main reason I don’t generally use them these days is because I plant 5 to 10 different varieties at a time, and I need to label my pots with the variety name. But if you just plan on growing one to three varieties, then the jiffy pots and compressed peat disks work fine.
Once your seeds have sprouted, they need light — from sunlight or a grow light. If you live in a chilly climate, grow lights might be your best bet. Where I live (South Florida), a windowsill works fine just about any time of year.
I hope all these tips have helped, and that you have much success in germinating tomato seeds!