When should I plant tomatoes in Minnesota?

The last week of May in most years. Wait until frost danger has passed, nights stay above 50°F, and soil reaches 60°F — in the Twin Cities north metro that consistently means about May 25 to June 1. Memorial Day weekend is the traditional marker, and it's a good one.

Can I plant tomatoes in early May in Minnesota?

Only with protection. Pre-warm the soil under black plastic and shield each plant with a water-filled protector or cold frame. Unprotected early-May tomatoes usually stall in cold soil and are often passed by ones planted three weeks later.

How late can I plant tomatoes in Minnesota?

Through mid-June for a full crop, especially early and cherry types like Sungold, Bush Early Girl, and Supersweet 100. After July 1, plant cherry tomatoes only and expect a smaller, later harvest.

What temperature kills tomato plants?

Frost — 32°F — kills or badly damages tomatoes overnight. Below about 50°F they stop growing and drop blossoms even without frost, which is why warm nights matter as much as the last-frost date. Cover plants with fabric (never bare plastic on leaves) when a cold night threatens.

Minnesota & Seasons

When to plant tomatoes in Minnesota

The short answer: the last week of May. In the north metro, tomatoes go in the ground once frost danger has passed, nights hold above 50°F, and the soil has hit 60°F — which almost always means May 25th to June 1st here. Memorial Day weekend is the traditional green light for a reason. Planted then, a tomato passes one planted in early May by July, because tomatoes don't grow in cold soil — they sit and sulk in it.

The three checks that matter

First, frost: East Bethel's average last frost lands mid-May, but "average" means half of years bite later — and one frosty night ends a tomato. Second, nights: below 50°F, tomatoes stall and drop blossoms even without frost. Third, soil: 60°F at planting depth. A $10 soil thermometer settles it, or use the old-timer test — if the soil feels cold to your bare hand at 9 a.m., it's not ready.

From the benchThe week we sell the most tomato plants is almost never the right week to plant them. Buy early for the best selection, then let them harden off on the porch — a few hours outside the first day, working up to overnight — while the soil catches up.

Want to cheat earlier? Here's how

Mid-May planting works if you pre-warm the bed under black plastic for a week and protect each plant — water-filled tomato protectors are good to several degrees of frost, and a wall of straw bales or a cold frame buys nearly as much. Containers are the other cheat: a black pot on a south wall warms weeks ahead of garden soil, and our Patio and Sun Dipper types are built for exactly that. If frost threatens after planting, cover with fabric — sheets, frost cloth — never bare plastic touching leaves.

Too late? Almost never

Tomatoes planted through mid-June still ripen a full crop here, especially quicker types — in our lineup, Sungold and Bush Early Girl are the ones we point at for late starts, and cherry types like Supersweet 100 and Yellow Pear come on fast once heat arrives. Past July 1st, stick to cherries and keep expectations August-sized.

Set them up right on day one

Full sun — eight hours if you can get it. Plant deep: bury two-thirds of the stem, even sideways in a trench; every buried hair becomes root. Water in well, mulch after the soil is fully warm (mid-June), and cage the big ones at planting — a Brandywine Pink or Big Beef at 72″ does not negotiate with a cage installed in July.

We grow twelve tomato varieties chemical-free — from San Marzano sauce types to Cherokee Purple — and we'll tell you straight which suit your spot and your calendar.

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When to plant tomatoes in Minnesota

The three checks that matter

Want to cheat earlier? Here's how

Too late? Almost never

Set them up right on day one

Get the spring heads-up