All plants

Arugula

Eruca vesicaria subsp. sativa

Brassicaceae · cabbage family

Matures
35–49 days
Harvest
Over a period · Annual
Sun
4–8 hrs
Spacing
2–6 in
Botanical engraving of Arugula

Planting window

When to sow, by microclimate — foggier blocks run a different calendar than sunnier ones.

JanFebMarAprMayJun
Foggy
Sunny
JulAugSepOctNovDec
Foggy
Sunny
Well-suitedMarginalNot suited

Sunlight

How well it does at each level of direct sun per day.

<2 hrsNot suited
2–4 hrsMarginal
4–6 hrsWell-suited
6–8 hrsWell-suited
8+ hrsMarginal
Well-suitedMarginalNot suited

Soil depth

Root room it needs — useful for sizing raised beds and containers.

6–10"Well-suited
10–15"Well-suited
15–18"Well-suited
18–24"Well-suited
Well-suitedMarginalNot suited

Spacing

Room each plant needs — along the row and between rows — for sizing beds.

In-row
2–6 in
Between rows
12–24 in

Growth habit

The shape it makes in the bed and how tall it gets — what tells you whether to give it a trellis, a stake, or just room.

Habit
Low mound
Mature height
12–18 in

Low and self-supporting — no staking needed.

How to start it

Sow it where it grows, or raise it under cover and set it out — and how far ahead to start the seedlings if it's the latter.

Usually
Direct-sow
Start indoors
4 weeks ahead
Direct-sowWell-suited
TransplantWell-suited

Sown straight into the bed it will grow in.

Well-suitedMarginalNot suited

Getting started

How it goes in the ground — how deep to sow or set it, and the soil temperature it needs to wake up. The cold-soil floor is the real limiter for direct-sowing in a foggy SF spring.

Started from
From seed
Ideal soil temp
60°F
Sow depth
0.25–0.5 in
Time to emerge
4–7 days

Germinates between 40–85°F; happiest around 60°F.

30°F110°F
IdealWorkable

Pests & diseases

What tends to trouble this crop — what it is, what you'll see, and what to do about it, least-toxic first.

Shares the leafy cole-crop pest complex — see kale, broccoli, and cabbage.

Pests3

Aphids
What it is
Aphids have soft pear-shaped bodies with long legs and antennae and may be green, yellow, brown, red, or black depending on the species and the plants they feed on. A few species appear waxy or woolly due to the secretion of a waxy white or gray substance over their body surface.
What you'll see
Low to moderate numbers of leaf-feeding aphids aren't usually damaging in gardens or on trees. However, large populations can turn leaves yellow and stunt shoots; aphids can also produce large quantities of a sticky exudate known as honeydew, which often turns black with the growth of a sooty mold fungus.
What to do
Before planting vegetables, check surrounding areas for sources of aphids and remove these sources. On the other hand, these aphid-infested weeds can sometimes provide an early source of aphid natural enemies.
Source
Cabbage Worms and Loopers
What you'll see
Worms and loopers are light to dark green. Adult loopers are gray or brown moths while cabbage worms are white butterflies. Worms and loopers chew holes in leaves and hide in kale heads.
What to do
Control worms and loopers with appropriate insecticides or biological measures.
Source
Flea Beetles
What it is
Their small size, enlarged back legs, characteristic shot-hole damage, and habit of jumping when disturbed make flea beetles easy to identify. There are numerous flea beetle species.
What you'll see
Adults feed mostly on leaves, leaving tiny pits or small holes at their feeding sites. Flea beetles feeding together can cover leaves with bleached, pitted areas or ragged holes.
What to do
Remove debris in the fall to remove any overwintering beetles. Reflective mulches applied very soon after planting and before plants become infected can be helpful.
Source

Sources

Every figure above is backed by these.

  • UC Master Gardeners, San Mateo–SF Countiesbacks plantingWindow · Foggy & Sunny calendars, Mustard row used as the mustard-family proxy for arugula (SF calendar has no arugula row; Sonoma groups arugula with mustard/Asian greens): seed foggy Jan-Oct, sunny Jan-Apr & Aug-Sep. Provides the Foggy/Sunny split.
  • Golden Gate Gardening (Pam Peirce)backs plantingWindow, lifecycle, harvestStyle · Foggier/Sunnier planting-times charts, Mustard row (mustard-family proxy): foggy Jan-Mar & Jul-Sep, sunny Jan-Mar & Jul-Sep; used to soften SF-calibrated edges to maybe. Habit and harvest: annual, over-a-period — from this source's entry for this crop.
  • UC Master Gardeners, Marin Countybacks plantingWindow, sunlight, soilDepth, inRowSpacing, daysToMaturity, plantingDepth, growthHabit · Arugula grow sheet (names Eruca vesicaria ssp. sativa): 'needs full sun ... will tolerate some shade' (sunlight); 'shallow rooting' (soil depth); 'Thin plants in the rows to six inches apart' (spacing); harvest ~5-7 weeks = 35-49 days; season Feb-May & Sep-Oct, cool-preferring/bolts in heat (corroborates window). Planting depth 1/4-1/2 in: 'Cover with one-quarter to a half-inch of soil.' Growth habit: 'Roquette' 'grows 12 to 18 inches tall before bolting' (and 'Dragon's Tongue' to 18 in), a leafy rosette classified low-mound at 12-18 in.
  • UC Master Gardeners, Sonoma County (Planting Summary)backs daysToMaturity, inRowSpacing, rowSpacing, startMethod · Vegetable Planting Summary, 'Greens, assorted' row (notes name Arugula explicitly): 35-45 days, 2-6 in in-row spacing. Between-row spacing 12-24 in (Greens, assorted row). Start method: Vegetable Planting Summary, Greens, assorted row: method D (usually direct-sown) — the row covering arugula.
  • Cornell University Home Gardeningbacks germination · Cornell arugula: germination 45–85°F, 60°F optimum, as low as 40°F; emergence 4–7 days
  • USDA GRIN Taxonomybacks botany
  • UC Master Gardeners, Santa Clara Countybacks startMethod · Start method: Planting chart: Arugula carries both a Transplant row (4 weeks from seed to transplant) and a Direct seed row.