TOMATOES

Who doesn’t love homegrown tomatoes? I think most of us do, and I’d say they are my favorite thing to grow. Every time I buy a tomato from the grocery store I tell myself it wasn’t worth the bother or the money and tell myself never do that again. But, there always comes a time I don’t have a garden, there’s red tomatoes at the store, and I cave in and buy them anyway. Even if they are organic and have a nice color, they’ll usually end up having no flavor. The first tomato I picked from the garden here, after my hiatus during our move, reminded me once again of the magnificent flavor of homegrown! It certainly is worth it to grow your own.

GROWING TOMATOES AT HIGH ELEVATION

Upon moving here, I knew from the start that growing tomatoes at this elevation would be a challenge and I may not be successful. I’d heard that it is possible to grow tomatoes here with special care and extra warmth at night, so I was ready with whatever I could do short of building a greenhouse (at that time).

My plan that first year here was to grow tomatoes in a bed that would be covered every night with plastic. On the coldest nights, frost cloth would also be laid over the tomatoes as a blanket for added warmth. Dark colored plastic bottles filled with water and placed around the tomatoes could soak up warmth from the sun during the day, to be released at night inside the plastic dome.

I grew just one bed of tomatoes: Glacier (55 Days), Coldset (65 Days), Siletz (65 Days): All these are determinate tomatoes, chosen based on cold-hardiness and early maturity.

They had 6 weeks of growth prior to transplanting outdoors. In my experience, giving tomatoes more indoor growth did not produce a better plant, nor produce an earlier harvest, so I stuck with 6 weeks. Tomatoes were planted outdoors on June 15th.

The first tomato I was able to harvest was the Glacier, 79 days after transplant. Several more tomatoes of all varieties were harvested between this date and September 23, when all remaining tomatoes were harvested prior to a freeze. Many of these tomatoes were green to yellowish-green, and I was able to ripen them indoors. At that time, our greenhouse had just been built, so they were placed on racks in the greenhouse until ripe. They were a bit mealy and didn’t have as much flavor as the vine-ripened tomatoes, but I had done all I could.

CONCLUSION: Although I did get some tomatoes from the outdoor garden, I decided that due to the inconsistent summer weather, the need to constantly watch and cover the tomatoes nightly, and the high probability of frost/cold in early September, I’d only grow tomatoes in the greenhouse in the future, even in the summer months. Typically we only get a couple nights all summer that are 50° or more. Due to the small size of the greenhouse I won’t be planting large numbers of tomatoes for canning projects as I did in our previous garden, but will only keep a few for eating fresh.

HIGH ELEVATION GROWING TIP: TOMATOES

Tomatoes really grow best greenhouse here, but don’t have one and and you live lower than 9,000′, give a couple of tomatoes a try outdoors. Choose a cold-hardy variety with the shortest # of maturity days.

Start your tomato plants indoors, about 6 weeks prior to your average last frost date. Transplant them out after the last day you think it will be freezing, and keep them covered every night throughout the summer if your temps are under 50°F.

If your tomatoes don’t ripen prior to freezing temperatures in the fall, just ripen them indoors and plan a greenhouse for future year-round tomatoes.

MOUNTAIN GREENHOUSE TOMATOES

With our greenhouse heated year-round to no less than 55ºF, tomatoes are now grown exclusively in the greenhouse. We almost always have about five tomato plants either growing or bearing fruit. They’re grown in succession, so every couple of months it seems I’m starting a couple more. It is possible for the tomatoes to continue to grow and produce for a year or more, but I usually remove them before that to keep rotating the plants in each section of soil. I anticipate when various plants (cabbage, lettuce, etc.) will be harvested, and start growing a new tomato for the spot 4-6 weeks before the other plants will be harvested.

Since I use the greenhouse year-round, I do the best I can to rotate plants and keep the soil replenished between plantings. Please see more about this in “Growing Food in the Greenhouse.” For the summer months I have discovered that the tomatoes grow better in the back half of the greenhouse near the deck overhang, where they get less direct sun. In the winter I am able to grow them in the front row, near the warm windows.

There is one central post in the greenhouse where I typically grow 1-2 indeterminate tomatoes. I train them up the post and across, hanging from the beams. I’ve also grown the indeterminate varieties up the side of the wall to extend across the beam in the same way. The remainder of the tomatoes are determinate, shorter plants. I occasionally put one or two cherry tomatoes in a hanging basket.

SELECTION: For the greenhouse I’m not so concerned about “days to maturity” since I knew there is warmth in the greenhouse indefinitely. However, I find that during the fall, winter & early spring months, keep in mind that it takes a LONG time for the tomatoes to grow, much longer than the maturity dates listed. I’m talking about up to 150 days from transplanting to the greenhouse to first tomato harvest, for a plant started in September. For this reason, I try to plant my earlier-producing tomatoes during these months. Not only does it take a long time for the plant to grow, once the tomatoes are set it takes a long time for them to ripen, and sometimes the winter tomatoes are a bit mealy. Still, they are tomatoes are good enough for a spaghetti sauce or tomato soup. As of this update (March 2023) I just made a big batch of tomato soup a few days ago.

Even in the summer months, the tomatoes take longer to reach maturity (first harvest) than the variety suggests, but not nearly as long as during the winter months. I’m not sure why.

One of the things I like to see when choosing tomato varieties, is those that are resistant to “blossom end rot” (BER), as I frequently find this to be a problem in my greenhouse. This is probably due to the fact that I’m constantly reusing the soil. I replenish it the best I can with compost, vermicompost, fertilizer, gypsum & eggshells (for calcium), bone meal, etc. Then, as tomatoes are growing I periodically spray the leaves with a calcium spray. With all this treatment, I still occasionally deal with blossom end rot on a plant or two.

STARTING: I always start my tomatoes in soil blocks. I start them in the 2″ size “mini” block, then usually transplant them to the “maxi” size before transplanting to the greenhouse bed. This process usually takes around 6 weeks. Occasionally I’ll plant the tomato in the the greenhouse bed directly from the 2″ block, but I find that they do much better when given time in the maxi block prior to transplant.

GROWING: While tomatoes are growing in the greenhouse, I use an organic fertilizer formulated specifically for tomatoes, and apply it faithfully according to the package instructions. I’ve gotten a few different brands and don’t really have a favorite, but I prefer using a liquid fertilizer due to its ease of use. As mentioned above I spray with calcium spray every 2-3 weeks, between the other fertilizer applications, a bit more often if I suspect BER.

I prune off the first, lowest stems before they begin to flower, to keep them ventilated and up off the soil. For the determinate tomatoes, I find that winter-planted tomatoes typically don’t grow as tall, and really need this pruning. After the first crop of tomatoes have been harvested, the plant will often take a bit of a break, then I will see many new shoots coming off the plant to give me another crop. It will begin to grow every-which-way and look kind of goofy, but I will get lots more tomatoes as the plant continues to produce. Eventually, I decide I just don’t want the plant anymore, usually because I want the spot for something else. At that point, I’ll start pruning off all new growth and keep it pruned while it ripens the remaining tomatoes. Then I’ll remove the plant.

Generally I use the tomatoes to eat fresh, however I’ll often have enough to do a small bit of canning. One of my favorite things is a sweet chile sauce that I like on hamburgers, so I do a small batch of that almost every summer. Other than that, I use extra tomatoes for various pasta recipes, often in the Instant Pot.

FAVORITE TOMATO VARIETIES FOR THE GREENHOUSE

I’m kind of a tomato seed nut… I keep looking for the perfect tomato variety and am often distracted by the “bright shiny objects” seen in emails and catalogs from seed companies. Or, sometimes a variety does well once, but never again, for some reason. I’m also trying to buy more heirlooms (open-pollenated) and fewer hybrids, so I can save the seeds. Here I’ll list some of the most consistent favorites in my greenhouse. I don’t always remember to write down the day of first harvest, but “DTH” indicates Days-To-Harvest in my greenhouse, winter/summer, as I have the records.

EXPLORE THE VEGGIES WE'VE GROWN AT 9000'

Laurie
November 17, 2019
Revised January 2024