How to Grow White Mustards USA

At a Glance

Quick Facts

Factor	Value
Drainage	Fertile, well-drained (RHS); NDSU: avoid drought-prone sandy soils, prefers good moisture.
Lifecycle	Annual herbaceous plant.
Edible parts	seeds, leaves

Growth Stages

Stage	BBCH	Notes
Sowing	0	NDSU: sow late April to mid-May, 0.5-1.5in deep into a moist, firm seedbed via drill or air seeder -- early planting on a firm seedbed supports vigour. RHS: propagate by seed into fertile, well-drained soil in full sun.
Seedling establishment	1	NDSU: flea beetles cause early-season "shot-holed" damage on seedlings -- treatment is only warranted once defoliation exceeds 25%. Cool temperatures and good moisture at this stage extend flowering and boost eventual yield.
Flowering	6	RHS: bright yellow flowers appear from May through to August or September, valued as a food source for wildlife.
Pod maturity and harvest	8	RHS: flowers are followed by dark red-to-brown seeds. NDSU: harvest by straight combining once pods are mature and dry, ideally at 12-15% seed moisture, around 85-90 days from sowing.

Harvest & Storage

When to pick: NDSU: harvest by straight combining once pods are mature and dry, ideally at 12-15% seed moisture for best quality -- crop matures 85-90 days from sowing.

Storage

Store dried seed in an airtight container; used to make table and hot-dog mustard, or in processed meats for flavour, emulsification and water binding (NDSU).

Diseases

Clubroot

moderate

Plasmodiophora brassicae

Named by RHS as the main UK disease risk for this brassica-family crop; NDSU's commercial-growing guidance does not mention it, instead flagging Sclerotinia -- a genuine regional difference kept honest rather than…

White mold (Sclerotinia stem rot)

moderate

Sclerotinia sclerotiorum

Named specifically by NDSU as a serious risk in commercial mustard production; recommends avoiding rotation with canola, sunflower or beans to reduce the risk.

Pests

Cabbage caterpillars

low

Pieris brassicae; Pieris rapae; Pieris napi; Mamestra brassicae; Plutella xylostella

Named by RHS as a general risk for this brassica-family crop.

Flea beetles

moderate

Chrysomelidae: Alticini (various spp.)

Named independently by both RHS and NDSU -- NDSU describes a "shot-holed" leaf appearance on seedlings, treatment warranted only above 25% defoliation.

Sources

1. North Dakota State University Agriculture Extension - Tame Mustard Production

   Soil: fertile, well-drained, avoid drought-prone sandy soils. Size: 30-45in height, matures 85-90 days. Climate: prefers cool temperatures and good moisture, which extend flowering and boost yield. Planting: seed late April to mid-May, 0.5-1.5in deep in a moist, firm seedbed; ~100,000 seeds/lb, sown at 10-14lb/acre via grain drill or air seeder; early planting and a firm seedbed support vigour. Pests: flea beetles cause early-season "shot-holed" damage on seedlings; treat if defoliation exceeds 25%. Diseases: Sclerotinia (white mould) a serious risk -- avoid rotating with canola, sunflower or beans. Harvest: straight combine when mature and dry, ideally at 12-15% seed moisture for quality. Edible use: table and hot-dog mustard; used in processed meats for flavour, emulsification and water binding.

These source is specific to this region. The full list of 2 sources behind this guide (North Dakota State University Agriculture Extension, Royal Horticultural Society) is in the references of our UK guide to white mustards; they describe the plant itself, which is the same wherever it grows.