Why it’s Better to Pressure Can Tomatoes

Image: University of Wisconsin Extension Service

Image: University of Wisconsin Extension Service

As most avid canners know, 4.6 is the pH dividing line between acid foods that can be safely water bath canned and less acidic foods that need to be canned in a pressure canner. Most fruits have a lower, i.e. more acidic pH and can be water bath canned.

Tomatoes, on the other hand, are often near the 4.6 pH level and USDA tested recipes will call for adding either bottled lemon juice or citric acid (I prefer citric acid as the taste is more neutral).

I used to think that this issue was because different tomato varieties vary in their acid content. It turns out that it’s more about when tomatoes are harvested, not to mention what the weather was like during the growing season. Add this variability to other factors, such as how many cans you put in your canner, the material your pot is made out of and the type of heat source and you end up with a tricky question for the food scientists who test home canning recipes. All of these factors are why the recommended hot water bath canning time for raw packed tomatoes is 85 minutes.

I’ve hot water bath canned tomatoes and got great results (especially with San Marzano tomatoes). But 85 minutes is a long time. You can cut the processing down considerably and get better results by pressure canning tomatoes. Here’s a raw pack recipe that includes both hot water and pressure canning instructions. Note that you still need to acidify.

Thanks to Linda Harris, UC Cooperative Extension Specialist, Food Safety and Microbiology who gave a lecture at the Master Food Preserver conference where I gleaned these factoids.

How To Diagnose a Tomato Disease

tomato mosaic

Tomato mosaic. Photo: Texas A&M.

It’s that time of year in the Northern Hemisphere. If you’re lucky you’ve got tomatoes. If you’re unlucky you’ve got tomato diseases.

When I’ve got a tomato problem I turn to Texas A&M AgriLife Extension’s Tomato Problem Solver. What makes it handy is all the pictures. They’ve pretty much covered every tomato disease in pornographic detail.

How are your tomatoes doing? Any problems?

How to save tomato seed

tomato seeds rotting in water

Seeds fermenting in water. Not pretty, but pretty important! The jar got shaken up while walking it outside for its photo op., so it looks a little cloudy and messy. In your jar, you should see a layer of scum on top of the water.

I can’t believe we haven’t posted about this before–it seems like we have, but I can’t find the post if this is so. Perhaps we wrote about it in one of our books…the old brain is getting foggy.

It’s easy to save seed from your favorite tomatoes. Seed saving in general is actually a little tricky. You can’t just save the seed from any old vegetable in your garden and hope that it will yield plants like the parent. Cross-breeding is an issue. Professional seed savers use all sorts of sacks and screens and boxes to ensure that busy bees or flirtatious winds don’t make romance happen where it ought not. Otherwise you get acorn squash crossing with melons and who knows what not. It depends on the type of vegetable you want to save seed from–as well as what else you’re growing around it.

Tomatoes, however, are a pretty safe bet for seed saving. They are self-fertile, and the structure of their flowers makes cross pollination difficult. Our seed saving Bible, Seed to Seed, says that there are only three types of open pollinated tomatoes that you can’t save seed from (without putting them in isolation):

  1. Currant tomatoes (L. pimpinellifolium)
  2. The potato leaved varieties of L. lycopersicum
  3. Any fruit born from double blossoms on Beefsteak-type tomatoes. Double blossoms are prone to cross-pollination.  You can save seeds from fruit that came from a single blossom

Odd, but simple! You can basically save seed from almost any heirloom/open-pollinated variety you’re likely to  be growing. You cannot save seed from hybridized plants. These are the type you are most likely to find in the nursery–plants bred for performance, not seed saving. This would include popular breeds like Early Girl and Better Boy and Sun Golds.  If you’re not sure if your tomatoes are hybrids or not, just Google the name. The Internet is wonderful that way.

The process of saving tomato seed is simple. All you have to do is rot off the protective gel sack which surrounds each seed. This gel inhibits germination, keeping the seeds from germinating while still in the tomato. In nature, the gel rots off while the fallen tomato sits on the ground. Here, you will speed the process along with some water. In addition to removing the gel sack, this fermentation process also kills many seed-borne tomato diseases.

How to Save Tomato Seed

  1. Choose your best, tastiest tomatoes for seed saving.
  2. Scoop out the seed pulp and drop it into a jar. Or just squeeze a whole tomato over the jar.   It’s best to just squeeze cherry tomatoes. (You can use food processor, too, if you’re doing big batches.)
  3. Pour a little water over the pulp. It should cover the pulp by say, 2-3  inches or so.
  4. Cover the container and let it sit for a few days (3 days, roughly–weather makes a difference), until white or grey mold forms on the surface of the water. If you do a big batch, you will smell the rot. Don’t worry about it–just keep the dogs away! Watch for the mold to form and continue on to the next step. The mold may be impressively fuzzy, or it may just be a slight opaque slick on top of the water. Don’t let it sit in this state too long, or the seeds will start germinating in their bath.* If you’re in doubt as to whether it is ready, it’s ready. Far better to stop a little early than to let the seeds accidentally germinate.
  5. Pour off the moldy water, reserve the seeds.
  6. Add clean water back to the seeds and give the water a swirl. Let it settle. Any bad seeds will rise to the top. If they do, pour them off.
  7. Strain the seeds with a fine strainer (a teas strainer is fine for small batches) and spread them out to dry. They need to dry on something which will wick water away, because it is important that they dry quickly–otherwise they might germinate. Coffee filters work well, as do pieces of window screen, or paper plates. Tomato seeds stick to paper towels, so if you use those you may end up having to plant the seeds on their little bits of towel.
  8. Once they are bone dry, transfer to envelopes or glass jars for storage. Be sure to label!

*I just lost a batch to germination. I blame the heat. It didn’t seem like they’d be fermenting that long, but after I drained my seeds I saw the tiny little white nubbins poking out of the seeds. Now I have to begin again. This is one reason why you should not wait ’til your last tomato to think about saving seeds. Also, this is a reminder to keep a close eye on your projects!

ETA: We’ve had some comments from what I’ll call the Paper Towel School of seed saving, and I thought I’d amend this post to point out that another method is to just spread some tomato pulp on a paper towel and let it dry out. The seeds will stick to the towel, so you store the whole towel and when planting time comes next year, you tear the towel into tiny pieces and plant the pieces. This does save steps. The method described above is the Official Method, and the method I’ve always used. I’ve not tried the paper towel thing myself, but it seems sensible. However, as  I understand it, the fermentation process in the water bath method kills diseases, so it is considered good etiquette to put your seeds through this process if you plan to share them with others.

Also check out the comments for more on the mystery of cross-pollinating tomatoes!

Matt’s Wild Cherry Tomato

Matt's Wild Cherry

Matt’s Wild Cherry image from Johnny’s Select Seeds.

Permaculturalist Paul Wheaton was in our neck of the woods this weekend to give a couple of lectures. In his talk on “Irrigation Free Foodscapes” he mentioned a variety of tomato called “Matt’s Wild Cherry” that, as the name implies, is a wild-type tomato that grows without supplemental irrigation.

Many avid vegetable gardeners have probably had the experience of tomatoes that reseed and grow without care. In my experience these hardy rogue tomatoes are invariably on the cherry side of the tomato size spectrum. This makes sense as the tomato’s wild ancestor is much smaller than modern beefsteak varieties.

Matt’s Wild Cherry was obtained in Hidalgo, Mexico by Teresa Arellanos de Mena, a friend of  agronomy professors, Dr. Laura Merrick and Dr. Matt Liebman. Johnny’s and other sources describe it as a small current sized tomato that readily reseeds.

Johnny’s Select Seeds carries it, and I’m considering giving it a try to supplement the tomatoes that reseed themselves in our garden. Let us know in the comments if you’ve tried Matt’s Wild Cherry or have tried any other wild-type tomatoes.

Tomato Report: Indigo Rose

Another tomato I got to taste on my trip up California’s central coast was the striking, nearly black “Indigo Rose”. The Indigo Rose tomato was bred conventionally by Oregon State University specifically to have high levels of antioxidants. Those antioxidants are in the tomato thanks to a class of flavonoids called anthocyanin, substances which also give the fruit its dark color.

According to Oregon State,

Indigo Rose’s genesis began in the 1960s, when two breeders – one from Bulgaria and the other from the United States – first crossed-cultivated tomatoes with wild species from Chile and the Galapagos Islands . . . Some wild tomato species have anthocyanins in their fruit, and until now, tomatoes grown in home gardens have had the beneficial pigment only in their leaves and stems, which are inedible.

The size is somewhat bigger than a cherry tomato. The inside of the tomato is a dark red. The taste? Good, even though the one I tried had not matured yet. I’m going to consider growing these next year.

You can find out more about the Indigo Rose on the Oregon State Extension Service website.

Indigo Rose seeds can be purchased through Johnny’s Select Seeds.

Tomato Report: Blush

I think I’ve tasted my new favorite tomato variety: Blush. I got to tuck into a box of these delicious tomatoes at the farm of Shu and Debbie Takikawa near Los Olivos. Yellow with red streaks, Blush tomatoes have the perfect balance of sweetness and acidity.

The blush tomato was developed by geneticist and tomato geek Fred Hempel and are available via Seeds of Change.

Due to a series of gardening blunders that I’ll blog about at some point, we’re not going to have many tomatoes this summer from our yard. Thankfully I can visit Shu and Debbie’s stand at the Altadena Farmer’s Market on Wednesdays.

If you’ve grown Blush tomatoes please leave a comment and let us know how they did.

Top Tasting Tomato Varieties

Sakura Honey, image from the Master Gardeners of Frankly County

It’s the time of year to start figuring out what tomatoes to plant here in the northern hemisphere. How about using taste to decide? The Master Gardeners of Franklin County Pennsylvania do a taste test every year. Here’s the top ten from last year’s results:

1 Sakura Honey
2 Red Pearl
3 Five Star
4 Principe Borghese
5 Old Brooks
6 Arbason
7 Fabulous
8 Heritage Hybrid
9 Cherokee Green
10 SX 605

The top three (all grape varieties) are available from Johnny’s Selected Seeds. See the full results of the taste test here.

Also, if you’re still looking for inspiration, review the comments on our recent giveaway post. Folks left their favorites there, and their regions–it’s a treasure trove of climate-specific information. We should make a chart out of it our something. 

Link thanks to Ken Druse’s Real Dirt Podcast

Tomatoes in December

It ain’t pretty but I’m not complaining.

Note to self: the tomatoes that sprout on their own are always the healthiest. The cherry tomato above has reseeded itself for at least 12 years. Sometimes its offspring survive the winter and grow as a perennial. Our climate sort of permits this but occasionally a cold night will kill tomatoes off. And each year the fruit declines in quality.

This summer I transplanted two tomato seedlings that sprouted in the yard on their own. One turned out to be the offspring of the Italian red pear tomato I grow every year and the other a somewhat boring but prolific yellow cherry tomato.

It’s Christmas and all of these tomatoes are still growing and producing. I’ve got an unintentional food forest started here. One of these days I’ll just give up starting seeds and let nature do her thing!

Tomato Report II: Franchi Red Pear

Franchi’s Red Pear tomato is a beefsteak variety we’ve grown for several years. It tastes phenomenal either fresh or cooked. From the Seeds from Italy website:

This is an old North Italian variety specially selected by Franchi Sementi. It is an indeterminate red, pear-shaped beefsteak. An outstanding producer of huge (as in 8-18 ounce) very tasty fruit. Great fresh eating. Early for such a large plant (70-75 days).  This is not the small pear shaped tomato called red pear by US Seed companies. Pear shaped with vertical ribs . . . Really meaty containing few seeds. Indeterminate.

One problem I’ve had with it is that it’s not super productive, at least in my vegetable beds.  I also think I may have over-watered it this summer and, consequently, it’s not quite as flavorful as last year’s more “meaty” crop.

So what beefsteak varieties do you like? I’m looking for suggestions for next year–hybrids or heirlooms.

ETA:  Just thought of something that would be helpful–if you rec. a tomato, tell us where you live. It will really help others searching for a good tomato that works well in their climate.

Tomato Report: Franchi Red Cherry

I don’t have much to say about this variety from Franchi named, somewhat generically, “Red Cherry”. It grew well and is very productive considering the compact size of the vine. The taste, however, was acceptable but not exciting. This could be because of over-watering on my part.

I could find very little information about this tomato on the interwebs other than that it is an indeterminate, early variety that grows well in pots (though I grew mine in the ground).

In the interest of a sweeter cherry tomato I think next year I’m going to plant the reliable Sungold.

What’s your favorite cherry tomato? Leave a comment . . .

ETA:  Just thought of something that would be helpful–if you rec. a tomato, tell us where you live. It will really help others searching for a good tomato that works well in their climate. You know how it is: location, location, location…  And if any of you who have already rec’d one see this, feel free to pipe up again regarding your location.

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