Learn About Growing & Harvesting Tomatoes with Maria Bertucci

Why You Should Grow Tomatoes: 

Tomatoes are the glory of the summer garden and while all fresh homegrown food tastes beautiful, homegrown summer tomatoes are an incomparable flavor experience. Even if you don’t have a garden, a cherry tomato plant tucked into a pot on the front porch or back patio is the essence of the good life.

Everyone seems to have their favorite varieties and with hundreds to choose from, I try new ones every year. I make sure to have very early ripening types, paste types, cherry tomatoes and big beefsteaks for those summer BLTs. Tomatoes come in every color and as a general rule, the more deeply colored a tomato is the higher the antioxidant content. I make sure to grow a few purple and black types every year and even if they weren’t extra healthy, I think they are worth it for the beauty alone.

Sowing Tomatoes: 

Tomatoes are easily started from seed in Feb/ March and grown indoors under a light until the temperatures are warm enough to set out in May. If grown this way, plants will need to be growing in a minimum size of 4 inch pots by the time the last frost date rolls around, not left in small packs. They will need feeding during this period as well in order to reach their potential. Even if you use a potting mix that contains fertilizer, I’d still recommend feeding once a week with a balanced liquid type. I use diluted fish fertilizer but it does add a special aroma to the house.

Once the last frost date rolls around it’s important to harden off your seedlings for a week by gradually exposing them to outdoor conditions starting with a morning sun and little wind exposure until they are ready for a full sunny day.

Tomato starts are often available to purchase in March and April when it is still much too cold to plant them out. If you buy them as tiny plants in pack trays, the best thing to do is pot them on into 4 inch or larger containers, set up a tray that you can bottom water them from and keep them in a sunny windowsill or on a shelf with a grow light. They don’t like nights much below 40 degrees, so if you have a greenhouse make sure you are monitoring the temperature. 

One great trick you can use with tomatoes is to winter sow them. Most folks do this by cutting the top off of a clear milk jug on three sides so it is still attached, poking drainage holes in the bottom and filling with a good, moist potting mix and some fertilizer. You then sow your seeds, put the top back on and leave them out on the porch by the door so you can check on them. They sprout when conditions are right for them outside and I have to say my plants started this way are the earliest producers I have grown. I began doing this when I noticed that out in the open garden, I had self-sown tomatoes producing ahead of my greenhouse grown starts every year.

If you do decide to winter sow, it’s still a good idea to watch the weather and bring those baby plants indoors for the night if it is supposed to freeze. 

Growing Tomatoes:

Prep your tomato bed with a calcium preparation before planting, mix in some good rich compost and a balanced fertilizer. I always pound stakes in for each plant before I set plants out and it doesn’t matter to me if I’m growing a determinate (bushy) or indeterminate (vining) variety, I find that stakes are needed for both. I usually cut up an old cotton tshirt into 1 inch wide strips and use them to tie the plants up the stake as they grow–biodegradable and soft on the plants stems.

You can use tomato cages instead of stakes, they last a long time and there are some really nice quality ones available as well as colorful choices.

Some folks prune the suckers out of their tomato plants, I generally miss the window to do this and I still get gobs of tomatoes all summer. There are great diagrams online if you want to find out how to prune properly.

Pests & Disease:

In the PNW we are blessedly free from some tomato pests like the hornworm but we do have some challenges nonetheless. The biggest hurdle is ripening. Similar to corn, tomatoes love a warm night which the PNW doesn’t really provide. There are a few things you can do about this–try growing early ripening varieties or clever use of plastic. Red or Black plastic sheeting over the soil of your tomato bed in spring will significantly increase the soil temperature and reduce the speed of cool down at night around the plants. You could also use pvc and plastic sheeting to construct a grow tunnel over them– this is the most involved solution but likely the most effective as it will also keep your plants mostly protected from brown rot which can get you in the fall if it gets really rainy in early September. There are lots of great tutorials online about how to make a grow tunnel, they are fairly easily put together with common hardware store parts and there are also ready made kits available. If you just have one or two plants you can use a cloche or milk jug with the bottom cut out in the early season to accomplish the same goal of frost protection and a warmer immediate environment. Growing in containers that have the south facing wall of a building behind them is also hugely effective.

The other most common problems are blossom end rot, with paste tomatoes being the most affected, cracking due to heavy rains or over watering and brown rot. Blossom end rot is caused by calcium deficiency in the soil and can be prevented by mixing a powdered source into your soil before planting. You can use gypsum, bone meal, shell meal and many folks crush their eggshells from the kitchen all year and mix that in as well.

If your tomatoes start to get blossom end rot despite having prepped your bed with calcium you can also use a pump sprayer to foliar feed you plants with a liquid fertilizer and I have found this to be very effective. You can’t fix fruit that already have it but your new fruit sets will be ok if you keep up on the task.

Cracking is something that happens when a plant has just ripe fruit and drastically fluctuating soil moisture. You can prevent this somewhat by making sure your plants get regular water but I will say that overwatering truly affects the flavor of your tomatoes. I err on the side of dry and just pick regularly to use up any cracked fruits immediately.

Brown rot is a fungus that is always in the soil and can overtake a plant pretty quickly when the nights are cooling down and we get a lot of rain at the end of the season. Covering your plants is the best way to prevent it as is using mulches.

Harvesting Tomatoes:

Cherry tomatoes are usually the first to ripen and you can cut whole bracts of them off of the plant to speed harvest and because they look gorgeous in the kitchen. My main tip for harvesting tomatoes is to do it every couple of days and to take some Maldon salt out to the garden with you to eat them whole while you work. Often, I will snag some fresh basil leaves into the bargain and have the best of summer eating while I get my chores done.

Every family seems to have their own favorite summer tomato recipes, I hardly need add any to the mix. Just don’t miss out on storing them away for winter so you can use up every single one that comes out of the garden.

My favorite storage tip for those who are too pressed for time to can sauce is the following:

• Coat two rimmed baking sheets with coconut oil, maybe 3-4 TBS worth
• Slice your tomatoes in half and lay out in the sheet
• Sprinkle with sea salt, pepper and basil or thyme
• Take an Instagram photo of your beautiful work.
• Roast until they are browned a bit caramelized.

Make sure you taste them before you freeze them, they are the best concentrated summer goodness flavor.

You can eat these just as they are or on bread but to store them for winter, just pack them into freezer bags and get them out when you need some sunshine in December and January.