Plant Database / Cover & Soil Crops / Field Mustard
Cover & Soil Crops

Field Mustard

Brassica rapa
Brassicaceae (Mustard)

A fast brassica cover that smothers weeds and biofumigates the soil as it breaks down. Quick and cheap.

Cover cropBuilds soilCool-season
Field Mustard (Brassica rapa) illustration — Texas Roots plant database, by Jordan Polasek
Sun
Full sun
Water
Low
Soil
Tolerant
pH
6.0–7.5
Hardiness
Cool-season annual
Height
2–4 ft
Spacing
Broadcast
Days to harvest
Fast cool-season

What it is

Field Mustard (Brassica rapa) is in the Brassicaceae (Mustard) family. A fast brassica cover that smothers weeds and biofumigates the soil as it breaks down. Quick and cheap.

How to grow it

It wants full sun, water it low, and give it tolerant soil. Target a soil pH around 6.0–7.5. Space plants about Broadcast apart. Expect roughly Fast cool-season. Cool-season annual.

How it's used

Field Mustard is used: cover; young greens edible.

🔎 How to identify it

  • Bristly lobed leaves
  • Yellow four-petal flowers
  • Fast growth

Edibility

PartsYoung leaves
UsesCover; young greens edible
CautionTerminate before heavy seed set.
The grow guide

How to grow & propagate field mustard

Everything I've worked out about starting this one, keeping it alive through a Texas year, and turning one plant into many — free.

How to propagate field mustard

The cabbage family is a cool-season seed crop. Start the heading types (cabbage, broccoli, cauliflower) in trays 5–6 weeks before you want them in the ground; sow the fast roots and greens (radish, turnip, mustard, arugula) straight into the bed. They all cross with each other readily, so if you're saving seed, only let one variety of a given species flower at a time.

Growing field mustard in Texas

Give it full sun and tolerant soil. Match the spot to the plant and most of the battle is already won.

This is a cool-season crop. On the Texas Gulf Coast that means your real windows are fall and late winter, not summer — sow as the heat breaks in September–October and again in late winter, and you'll harvest through our mild winters while the rest of the country is frozen out.

Keep moisture even, especially while it's young — deep, less-frequent soaks build better roots than a daily sprinkle.

Harvesting

Figure on roughly fast cool-season before you're harvesting. The part you're after: young leaves.

Making more for free

If you want more, let your healthiest plants mature fully and collect the seed once it's dry on the plant — then store it somewhere cool, dark, and dry until next season.

🌤 Before you plant: check the live 7-day garden weather to time it right for frost and heat.

Part of the free Texas Roots plant database, compiled by Jordan Polasek from his greenhouse in El Campo, Texas. Free to read and share. If it helped, the best thanks is to grow something.