When to plant · 4 cities · zones 4b–5b

When to plant mustard greens in Montana

Direct sow mustard greens around May 20 — the Montana statewide median, counted from a last spring frost of May 20 across 332 ZIP codes and 181 NOAA stations.

May 20Direct sowMay 9 – Jun 6 across the state
May 20Last spring frostmedian · 1 in 10 years after Jun 4
Jun 19First harvest30 days from sow

The rule: Direct sow as soon as the soil can be worked in spring, and again in late summer for fall. Seed germinates fastest at 55–65 °F and may stall above 80 °F.

Montana mustard greens, by step

Statewide median last frost May 20, first fall frost Sep 22, 2027 season. Each cultivar's own indoor lead time and days to maturity, same engine as the Plan Builder.

CultivarStart indoorsSowFirst harvestDays
Mustard greensGarnet Giant (Brassica juncea)Direct sowMay 20Jun 1930 from sow

Tight means first harvest lands within two weeks of the median first fall frost. Statewide dates are the ZIP-weighted median of every NOAA 1991–2020 station Montana's ZIP codes resolve to; 37 of 369 ZIPs have no datable freeze and are left out.

Mustard Greens in Montana, city by city

Mustard greens, scheduled from each city's nearest NOAA station — the same dates as its frost page.

CityLast frostSowFirst harvest
Billingszone 5aMay 5May 5Jun 4
Missoulazone 5bMay 10May 10Jun 9
Great Fallszone 4bMay 6May 6Jun 5
Bozemanzone 5aMay 23May 23Jun 22

What Montana mustard greens need

StartSoil temperature and light intensity, indoors, weeks before your frost date.
  • Organic Seed Starter Potting MixMust have

    Seed-starting mix is not potting soil with a nicer label — it is finer, lighter, and low in nutrients on purpose, because a seedling's first roots want air and moisture, not fertiliser.

  • 72-Cell Trays with 1020 Bottoms, 5-PackMust have

    The cheap black nursery trays crack after one season and flex enough to break roots when you lift them. These do not. Over five seasons the price per use is lower than the throwaways.

ProtectFrost, hornworms, aphids, and the fungal pressure that follows a wet July.
  • AG-30 Frost Protection Row Cover

    AG-30 buys roughly 6 °F of frost protection while passing about 70% of light — enough to carry a crop through an early-October cold snap that would otherwise end your season two weeks short.

  • Ultra-Fine Garden Netting, 10×33 ft, 2 pcs

    A hornworm is a moth's decision made in June. Fine mesh over the bed at transplant means the moth never lands, and you never spray anything at all.

HarvestTiming, handling, and weighing what you actually got.
  • 6" Micro-Tip Pruning SnipsMust have

    Ninety percent of sauce-garden cutting is snipping a pepper stem or a basil node, and a fine-tipped snip does it better than any pruner. Pulling peppers by hand tears the branch.

  • Digital Kitchen Scale, 11 lb, g/ozMust have

    Fermentation brine is a percentage of weight, not a number of spoons. Without a gram scale you are not following a fermentation recipe — you are guessing at the one number that determines whether it is safe.

CookReduction, texture, and the non-reactive pans that keep tomato tasting like tomato.
  • One-Touch Coffee & Spice Grinder

    Dried cayenne into powder in fifteen seconds. Dedicate one to chiles — grind coffee in it afterwards and you will find out exactly how well capsaicin sticks to plastic.

PreserveTested processes, correct headspace, and jars that are still good next March.
  • Half Pint (8 oz) Regular Mouth Mason Jars, 12Must have

    Eight ounces is the right jar for a sauce you use by the spoonful. Open a quart of hot sauce and you are racing the fridge; open a half-pint and you finish it while it is still good.

Paid links. We earn a commission from Amazon if you buy; you pay the same. Disclosure.

Mustard Greens in Montana: questions

When should I plant mustard greens in Montana?

Direct sow around May 20 at the statewide median; across the state that date runs from May 9 in the warmest tenth of Montana's ZIP codes to Jun 6 in the coldest. To cut the freeze risk to one year in ten, count from Jun 4 instead of the median last frost. Use the city table for your own town.

When is the last frost in Montana?

The ZIP-weighted median of NOAA 1991–2020 station medians is May 20. In the warmest tenth of Montana's ZIP codes the median last frost falls on or before May 9; in the coldest tenth, on or after Jun 6.

When will Montana mustard greens be ready to harvest?

Mustard greens planted on the statewide date is ready around Jun 19: 30 days from sow.

More for Montana

Mustard Greens in every state → · Montana frost dates → · How frost-date math works →