Plant Paste Tomatoes If You Actually Want Sauce

Quick answer: Grow a paste tomato like Roma or San Marzano, not a slicer. Start seeds six to eight weeks before your last frost and plant out once nights stay above 50°F. Bury the stem deep and water on a schedule. Freeze every ripe one until you've got enough for a single big cook.

Picture the counter in mid-August. Three Brandywines the size of softballs, a bowl of Sun Golds, a few Better Boys with cracked shoulders. You put them all in a pot, and three hours later you've got two pints of something pink and thin that tastes like warm salad.

That isn't a cooking problem. It's a seed problem. Slicers are bred to be juicy, and juice is mostly water. Paste tomatoes have thick walls, few seeds and much less water, so they cook down into sauce instead of soup. If sauce is the goal, the most important decision of the season happens at the seed rack.

Choose the plant before you choose anything else

Paste tomatoes come in two growth habits, and the difference shapes your whole summer.

Determinate varieties like Roma and Rio Grande grow to a set size, usually waist-high, and ripen most of their fruit over a few weeks. That's exactly what you want for canning day. You get a wave of tomatoes, you cook, you're done.

Indeterminate varieties like San Marzano and Amish Paste keep growing and producing until frost kills them. Plenty of people think they taste better, and they'll give you sauce tomatoes from July into October. The cost is height. They'll top six feet and need real support, and you'll be cooking in smaller batches unless you freeze as you go.

Want one sandwich tomato? Fine. Put in a single Cherokee Purple for BLTs and keep it out of the sauce pot.

Then plant more than feels reasonable. The USDA's home canning guide figures roughly five pounds of tomatoes for a quart of thin sauce and closer to six and a half for thick. Six plants make a few good dinners. If you want a pantry, you need a bed full.

Your frost date sets the calendar

Tomatoes hate cold. Below about 50°F at night they sit there and sulk, and a frost kills them outright. The date that matters is your average last spring frost, which you can get from your county extension office. Your hardiness zone gets you in the neighborhood.

In much of zone 5, that frost date lands somewhere around mid-May. In zone 8 it can be late March. So the same plant goes in the ground two months apart depending on where you live, and copying a gardener from a different state is how people lose their first planting.

The South has the opposite problem. When days run above 90°F and nights stay warm, tomato flowers often drop without setting fruit. Down there, get plants in as early as frost allows so they set fruit before the heat. A second planting in midsummer can carry you into a fall harvest.

Start seeds, or buy smart

Starting your own is the only reliable way to get San Marzano or Amish Paste, because most garden centers stock Roma and call it a day. Sow six to eight weeks before your frost date. The full setup is in starting seeds indoors, but a few tomato-specific points matter.

• Keep the light two or three inches above the seedlings for 14 to 16 hours a day. A sunny windowsill isn't enough. Tall, pale, floppy seedlings are starving for light.
• Brush your hand across the tops once a day, or run a small fan. Stems that move grow thicker.
• Pot up once into a bigger cup when they have their first true leaves.

Before planting, harden them off for seven to ten days. Start with an hour outside in the shade, then add time and sun every day. Skip this and you'll get white, scorched leaves within a day of planting. It looks like disease. It's sunburn.

Buying transplants instead? Pick the short, stocky, dark green ones with no flowers yet. The tall plant already holding a tomato looks like a head start. It isn't, and it'll stall after transplant.

Plant deep and put supports in on day one

Give tomatoes at least eight hours of direct sun. Less than that and you'll grow a lovely green bush with a handful of fruit.

Strip off the lower leaves and bury the stem up to the top few sets. Tomatoes grow roots all along a buried stem, so a deep plant is a stronger, thirstier, better-anchored plant. If a seedling is leggy, lay it sideways in a shallow trench and bend the top up gently. It'll straighten within days.

Space determinates about two feet apart and indeterminates two to three. Mix compost into the hole and use a balanced fertilizer at planting. Go light on nitrogen. Heavy nitrogen gives you a jungle of leaves and very little fruit.

Set your support the same day. Drive a stake in July and you'll spear the roots. Those flimsy cone cages from the hardware store are fine for peppers and will fold under a loaded indeterminate by August. Use a tall stake, or make cages from concrete reinforcing wire, which will outlast your truck.

Once the soil has warmed, mulch two to three inches deep with straw or shredded leaves. It holds moisture, and it keeps soil from splashing onto the leaves, which is how a lot of disease starts. And don't plant tomatoes in the same spot two years running if you can help it.

What goes wrong in July

Black, leathery bottoms. That's blossom end rot, and Romas are known for it. It comes from the plant failing to move calcium into the fruit, and the usual cause is uneven watering, not a lack of calcium in the soil. Crushed eggshells won't fix it. Steady water will. Aim for one to two inches a week, more in a heat wave, delivered deep at the base in the morning. Pick off the affected fruit. The next ones are usually fine once watering evens out.

Cracked fruit. A dry spell followed by a hard rain makes the tomato swell faster than its skin can stretch. Even watering and mulch prevent most of it.

Stripped branches overnight. Look for hornworms, big green caterpillars that are oddly hard to spot. Find the black droppings on the leaves below and look straight up. Pick them off by hand.

Brown spots with rings on the lower leaves. That's usually early blight. Prune off the bottom foot of leaves and keep water off the foliage. Stay out of the plants when they're wet, because you'll carry it from plant to plant on your hands.

Fruit that tastes flat. That's a whole topic of its own, from variety to watering to where you ripen them, and it's covered in why your tomatoes taste like water.

Pick early, freeze everything, cook once

Pick paste tomatoes when they first blush orange-red. Let them finish on the counter, stem side down and out of direct sun. Never in the fridge, which kills the flavor. Picking early also keeps the squirrels and the splitting rain from getting them first.

Now the trick that changes everything. Rinse the ripe ones, cut out the core and drop them whole into gallon freezer bags. Do it every few days all summer. When you've got a freezer drawer full, thaw them in a big bowl and the skins slide right off in your hand. Your harvest came in dribs and drabs, but your cooking day doesn't have to.

Roasted sauce, the easy way:

1. Halve the tomatoes and lay them cut side up on sheet pans with a quartered onion and a head's worth of peeled garlic.
2. Drizzle with olive oil and salt generously.
3. Roast at 400°F for about an hour, until the edges brown and the pans look dry.
4. Run everything through a food mill to drop the skins and seeds, or blend it if you don't mind them.
5. Simmer to the thickness you like and stir in fresh basil at the end.

Freeze it in quart containers with an inch of headspace for expansion.

Canning is a different animal. Tomatoes sit close to the line on acidity, so tested recipes call for bottled lemon juice, two tablespoons per quart, or citric acid. And adding onion and garlic changes the safety math. Keep the roasted, seasoned sauce for the freezer. For jars, follow a USDA-tested recipe exactly, and ask your extension office if you have questions.

If you borrowed a neighbor's food mill for the day, it goes back cleaner than you got it, with a quart in the box.

In February, you'll pull out a container that smells like August. By the time the pot boils, you'll be ordering next year's seeds.