How To Grow Arugula in Canada | Complete Guide

Download | How to Grow Arugula in Canada | Complete Growing Guide (PDF)

Unlike many warm-season herbs, arugula prefers the cooler temperatures of spring and autumn. This makes it particularly well suited to Canadian gardens, where gardeners can often enjoy an early spring harvest followed by another crop in the fall.

Whether you're planting in raised beds, traditional garden rows, or containers, this complete guide explains how to grow arugula from seed in Canada, including planting dates, germination, spacing, watering, succession sowing, preventing bolting, and harvesting fresh leaves.

Arugula Growing Guide at a Glance

Feature	Growing Requirement / Detail
Botanical Name	Eruca sativa (syn. Eruca vesicaria)
Plant Type	Annual, cool-season culinary herb and leafy green
Sun Exposure	Full sun to partial shade; afternoon shade is beneficial during warm weather
Soil	Fertile, well-drained soil rich in organic matter; pH approximately 6.0–7.0
Start Indoors	Optional, approximately 2–3 weeks before transplanting; direct sowing is usually easier
Direct Sow	Early spring, approximately 2–4 weeks before the last expected frost; sow again in late summer for fall harvests
Sowing Depth	Approximately 6 mm (¼ inch)
Germination	Approximately 4–10 days in suitable conditions; slower in cold soil
Plant Spacing	10–15 cm (4–6 inches) for mature leaves; closer spacing for baby greens
Row Spacing	Approximately 20–30 cm (8–12 inches)
Water Needs	Moderate; maintain consistent soil moisture for tender, flavourful leaves
Difficulty Level	Easy
Container Friendly	Yes; excellent for containers, raised beds, and balcony gardens
Plant Height	Approximately 20–30 cm (8–12 inches) during leafy growth; flowering stems may grow taller
Harvest	Baby leaves: approximately 20–30 days; mature leaves: approximately 35–50 days
Best Uses	Fresh salads, sandwiches, pizza, pasta, pesto, and garnishes

What Is Arugula?

Arugula, also known as rocket or salad rocket, is a leafy green belonging to the Brassicaceae family. It is related to broccoli, cabbage, kale, mustard greens, and radishes.

Its deeply lobed leaves have a distinctive peppery, slightly nutty flavour. Young leaves are generally tender and mild, while older leaves develop a stronger, more pronounced taste.

Although arugula is often classified as a leafy vegetable, it is also widely grown as a culinary herb because of the flavour it adds to dishes.

Arugula is particularly valuable in Canadian gardens because it grows quickly, tolerates cool conditions, and can be planted more than once during the growing season.

Read More | How To Grow Lettuce in Canada | Complete Guide

Is Arugula the Same as Rocket?

Yes. Arugula and rocket are common names for the same culinary green. In North America, the name arugula is most commonly used, while rocket is more familiar in the United Kingdom and other regions.

Wild rocket, commonly associated with Diplotaxis tenuifolia, is a related but different plant that generally has narrower leaves and a stronger flavour.

When to Plant Arugula in Canada

For most Canadian gardeners, the first outdoor sowing can begin approximately 2–4 weeks before the average last spring frost, provided the soil is workable and not waterlogged.

Arugula germinates best in moderately cool soil, generally around 10–21°C (50–70°F), although germination can occur outside this range.

For a fall crop, sow again approximately 6–8 weeks before your expected first autumn frost. In mild regions, additional late sowings may be possible.

Canadian Arugula Planting Calendar

These planting windows are approximate. Local frost dates, soil conditions, and seasonal temperatures should determine your actual sowing dates.

Caribou Growing Note: Arugula Loves Cool Weather

One of the biggest advantages of growing arugula in Canada is that you don't need to wait for summer. Sow it early in spring while the weather is still cool, and plant another crop toward the end of summer. Spring and autumn harvests often produce more tender leaves with a milder flavour than crops grown during hot weather.

How to Grow Arugula from Seed

Step-by-Step Outdoor Sowing Instructions

1. Choose a Location: Select a sunny garden bed. During warmer months, a location receiving some afternoon shade is beneficial.
2. Prepare the Soil: Loosen the upper 15–20 cm (6–8 inches) of soil and incorporate finished compost where needed.
3. Check Soil Conditions: Wait until the ground is workable and no longer excessively wet.
4. Sow Seeds: Plant seeds approximately 6 mm (¼ inch) deep.
5. Space Rows: Leave approximately 20–30 cm (8–12 inches) between rows.
6. Water Gently: Moisten the seedbed thoroughly without displacing the seeds.
7. Maintain Moisture: Keep the soil evenly moist until germination.
8. Thin Seedlings: Thin to approximately 10–15 cm (4–6 inches) apart for mature leaves.
9. Harvest Regularly: Begin harvesting tender leaves once they reach a usable size.

For baby arugula, seeds may be sown more densely and harvested while leaves are still small. For larger plants and repeated leaf harvesting, provide additional spacing.

Arugula Seed Germination

Seeds germinate well in moderately cool soil. Temperatures around 10–21°C (50–70°F) generally provide good conditions, although emergence may be slower in colder soil.

Tips for Successful Germination

• Use fresh, high-quality seeds.
• Sow approximately 6 mm (¼ inch) deep.
• Keep the upper soil evenly moist during germination.
• Avoid planting in waterlogged or heavily compacted soil.
• Prevent the soil surface from drying out completely.
• Choose cooler spring or autumn conditions whenever possible.
• Thin crowded seedlings to encourage healthy leaf development.

Why Aren't My Arugula Seeds Germinating?

Common causes include dry soil, excessively wet conditions, planting too deeply, old seeds, or unsuitable soil temperatures.

During hot weather, the soil surface can dry rapidly, making it difficult for newly germinating seeds to establish. Light shade and careful watering can improve conditions.

If seeds have not emerged after approximately 10–14 days, check the soil moisture and temperature before reseeding.

Should You Start Arugula Seeds Indoors?

Arugula can be started indoors, but it is usually unnecessary. Because the plants germinate and grow quickly, direct sowing is generally the simplest approach.

Indoor starting may be useful for gardeners who want an especially early harvest or who are growing arugula in containers.

If starting indoors, sow seeds in individual cells approximately 2–3 weeks before the intended transplanting date. Provide strong light, keep the growing medium evenly moist, and transplant while seedlings are still young.

Harden seedlings off gradually before planting outdoors.

For most Canadian gardeners, direct sowing offers equally good results with considerably less work.

Soil, Sunlight and Fertilizing Requirements

Arugula grows best in fertile, well-drained soil that retains sufficient moisture for steady leaf growth.

A soil pH of approximately 6.0–7.0 is suitable. Incorporating finished compost before planting can improve soil structure and provide nutrients.

How Much Sun Does Arugula Need?

Arugula grows well in full sun during cool weather. In warmer conditions, partial shade can help reduce heat stress and delay bolting.

Approximately 4–6 hours of direct sunlight can support good leafy growth, although plants may grow more slowly in shadier locations.

Fertilizing Arugula

Arugula is a relatively light feeder compared with many fruiting vegetables.

In fertile garden soil enriched with compost, additional fertilizer may not be necessary for a short crop.

Where growth is slow or foliage appears pale because of nutrient deficiency, apply a balanced fertilizer or a modest amount of nitrogen according to product instructions.

Avoid excessive fertilizing, which can produce overly soft growth and is unnecessary for most short-season harvests.

How Far Apart Should Arugula Plants Be?

Spacing depends on whether you want baby leaves or mature arugula plants.

Overcrowded plants compete for water, light, and nutrients. Proper thinning encourages healthy growth and makes harvesting easier.

Watering and Mulching Arugula

Consistent moisture is one of the most important factors in producing tender, flavourful arugula leaves.

When plants experience drought stress, leaf growth slows and the flavour may become noticeably stronger or more bitter. Water stress can also contribute to premature bolting.

As a general starting point, provide approximately 2.5 cm (1 inch) of water per week, including rainfall, adjusting for soil type, temperature, and plant growth.

During warm weather, containers and shallow-rooted plants may need more frequent watering.

Mulching Arugula

Apply a thin layer of clean straw, shredded leaves, or other suitable organic mulch around established plants.

Mulching helps:

• Conserve soil moisture.
• Keep the soil cooler during warm weather.
• Suppress competing weeds.
• Reduce soil splashing onto leaves.

Avoid covering young seedlings with mulch or piling material directly against the stems.

Read More | How Often Should You Water a Vegetable Garden?

How to Prevent Arugula from Bolting

Bolting occurs when arugula shifts from producing tender leaves to developing flowering stems and seeds.

It is a natural part of the plant's life cycle, but it often happens earlier than gardeners would like during hot weather and long summer days.

Once arugula begins flowering, leaf production generally slows and the leaves often develop a stronger, more bitter flavour.

Common Causes of Bolting

• High temperatures.
• Long summer daylight hours.
• Dry soil or irregular watering.
• Plant stress.
• Natural maturity.

Tips to Delay Bolting

1. Plant Early: Sow arugula during cool spring weather rather than waiting until summer.
2. Grow a Fall Crop: Late-summer sowings often mature under more favourable autumn conditions.
3. Provide Afternoon Shade: During warm weather, partial shade can reduce heat stress.
4. Water Consistently: Avoid allowing plants to become severely dry.
5. Harvest Promptly: Pick leaves while they are tender and before flowering begins.
6. Sow New Crops: Replace aging plants with fresh seedlings rather than relying on one planting all season.

Pinching off a developing flower stalk may briefly delay flowering, but it will not reliably return a mature, bolting plant to vigorous leaf production.

Caribou Growing Note: Don't Fight the Summer Heat

Arugula is naturally a cool-weather crop. Rather than struggling to keep plants productive during the hottest weeks of summer, take advantage of Canada's cooler spring and autumn seasons. A fresh sowing in late summer can produce excellent leaves for fall salads, often with less bitterness and slower bolting.

Succession Planting Arugula for Continuous Harvests

Instead of planting an entire packet at once, sow a small amount every 10–14 days while temperatures remain suitable.

How to Succession Sow Arugula

1. Sow a short row or small block of seeds in early spring.
2. Wait approximately 10–14 days.
3. Sow another small section of seeds.
4. Continue planting at similar intervals while conditions remain cool.
5. Pause during prolonged summer heat if plants bolt rapidly.
6. Resume sowing in late summer for autumn harvests.

This method provides younger, tender leaves over a longer period rather than one large harvest followed by a shortage.

In mild Canadian regions, row covers or cold frames can extend the autumn harvest into cooler weather.

Read More | Maximize Harvests in a Small Garden | High Yield Picks

Growing Arugula in Containers

Its relatively shallow root system and compact growth make it particularly suitable for wide, shallow planters.

Choosing a Container

Select a container approximately 15–20 cm (6–8 inches) deep or deeper, with adequate drainage holes.

A wide container or window box provides room for several plants and allows easy harvesting.

Container Growing Tips

• Use a quality, well-draining potting mix.
• Direct sow seeds approximately 6 mm (¼ inch) deep.
• Thin seedlings according to the desired harvest size.
• Provide morning sunlight and some afternoon shade during hot weather.
• Check moisture frequently because containers dry faster than garden beds.
• Harvest regularly while leaves are young and tender.
• Sow new seeds every couple of weeks for continued production.

Containers can also be moved into a cooler, more sheltered location when summer temperatures rise.

Growing Arugula in Raised Beds

Raised beds are particularly well suited to arugula because they offer good drainage, easy access, and flexible planting arrangements.

In spring, raised-bed soil often becomes workable earlier than heavy garden soil. This can allow gardeners to begin planting sooner.

However, raised beds may also dry out and warm up more quickly during summer.

For best results, incorporate compost, maintain consistent moisture, and use light mulch where appropriate.

Arugula can be planted in short rows, blocks, or small spaces between other cool-season crops.

Read More | Raised Bed vs In-Ground Garden | What Should You Choose?

Common Arugula Pests and Diseases

Arugula belongs to the cabbage family and can attract some of the same pests that affect kale, broccoli, cabbage, and other brassicas.

When and How to Harvest Arugula

Baby leaves may be ready approximately 20–30 days after sowing, while larger leaves typically develop within approximately 35–50 days, depending on growing conditions.

Harvesting Baby Arugula

Baby arugula is harvested while leaves are small, tender, and relatively mild.

Leaves approximately 5–10 cm (2–4 inches) long are ideal for many salad uses.

Use clean scissors to cut the leaves above the growing point, or harvest individual leaves as needed.

Harvesting Mature Arugula Leaves

For repeated harvesting, pick the larger outer leaves while leaving the central growing point intact.

1. Choose healthy plants with well-developed foliage.
2. Harvest outer leaves approximately 10–15 cm (4–6 inches) long, or at your preferred size.
3. Use clean scissors or gently pinch leaves near their bases.
4. Leave the central leaves and growing point undisturbed.
5. Allow plants to produce new foliage before harvesting again.

Regular harvesting can extend the useful life of the planting, although plants will eventually bolt as temperatures rise or they reach maturity.

Can You Harvest Arugula More Than Once?

Yes. Arugula can produce multiple harvests when the growing point remains intact and plants are kept healthy.

However, repeated harvests depend on the weather, plant maturity, and how much foliage is removed.

For the most consistent supply, combine repeat harvesting with succession planting.

Why Does Arugula Taste Bitter?

Arugula naturally has a peppery flavour, but excessive bitterness can develop as plants mature or experience stress.

Common contributing factors include:

• Hot weather.
• Bolting and flowering.
• Drought stress.
• Overly mature leaves.
• Natural differences in growing conditions.

For a milder flavour, harvest younger leaves, maintain consistent moisture, and grow arugula during cooler weather.

Older or strongly flavoured leaves can still be useful in cooked dishes, where their peppery taste may be less pronounced.

Growing Arugula for a Fall Harvest in Canada

Fall is often one of the best times to grow arugula in Canada.

As summer temperatures decline, conditions become more favourable for steady leaf growth and reduced heat stress.

Begin sowing approximately 6–8 weeks before your average first autumn frost, adjusting for local conditions.

Tips for Successful Fall Arugula

• Sow seeds while enough growing time remains before severe cold weather.
• Keep the seedbed moist during warm late-summer days.
• Provide temporary shade if germinating seeds during a heatwave.
• Thin seedlings once established.
• Harvest tender leaves regularly.
• Use lightweight row covers or cold frames to protect plants from increasingly cold conditions.

Established arugula can tolerate light frost, but severe freezing temperatures may damage leaves and eventually stop growth.

In mild coastal areas, protected plantings may continue producing well into late autumn or winter, although growth slows substantially as daylight decreases.

How to Store Fresh Arugula

Freshly harvested arugula is best enjoyed soon after picking, when the leaves are crisp and flavourful.

Refrigerating Arugula

1. Remove damaged or yellowing leaves.
2. Rinse gently in cool water if necessary.
3. Dry leaves thoroughly using a salad spinner or clean towel.
4. Place them in a container or produce bag lined with a dry paper towel.
5. Refrigerate promptly.

Properly stored arugula generally keeps for approximately 3–5 days, sometimes longer depending on freshness and storage conditions.

Avoid storing wet leaves in tightly sealed containers, as excess moisture encourages deterioration.

Can You Freeze Arugula?

Arugula can be frozen, but its tender leaves lose their crisp texture after thawing.

For freezing, arugula is better suited to pesto, sauces, soups, or other cooked preparations than fresh salads.

Read More | How to Store Fresh Vegetables After Harvest

How to Use Arugula in the Kitchen

Arugula's peppery flavour makes it a versatile ingredient in everyday cooking. It can be used fresh or lightly cooked, depending on the dish.

Grow Arugula from Seed Today

Enjoy fresh, peppery greens straight from your garden with Caribou Seed Company's Arugula Seeds. This fast-growing annual is an excellent choice for beginners, container gardeners, and anyone looking to grow fresh salad greens during Canada's cooler spring and autumn seasons. Shop Arugula Seeds at Caribou Seed Company

Download | How to Grow Arugula in Canada | Complete Growing Guide (PDF)

Frequently Asked Questions About Growing Arugula

Can you grow arugula in Canada?

Yes. Arugula grows exceptionally well in many Canadian gardens, particularly during the cooler temperatures of spring and autumn.

Is arugula easy to grow from seed?

Yes. Arugula is a fast-growing, beginner-friendly crop that generally germinates quickly and requires relatively little maintenance.

When should I plant arugula in Canada?

Plant outdoors approximately 2–4 weeks before the average last spring frost, once the soil is workable. Sow again in late summer for a fall harvest.

Does arugula need full sun?

Arugula grows well in full sun during cool weather. Partial shade, particularly in the afternoon, can help during warmer conditions.

How deep should I plant arugula seeds?

Sow seeds approximately 6 mm (¼ inch) deep.

How long does arugula take to germinate?

Arugula typically germinates within approximately 4–10 days under favourable conditions.

How long does arugula take to grow?

Baby leaves may be ready in approximately 20–30 days, while larger leaves generally take approximately 35–50 days.

Can arugula tolerate frost?

Yes. Established arugula tolerates light frost, making it suitable for early spring and fall growing. Severe freezing conditions can damage the plants.

Can arugula grow in containers?

Yes. Arugula grows well in containers approximately 15–20 cm (6–8 inches) deep or deeper, provided they have good drainage.

How far apart should arugula plants be?

Space plants approximately 10–15 cm (4–6 inches) apart for mature leaves. Baby greens can be grown more closely together.

Why is my arugula bolting?

Arugula commonly bolts in response to hot weather, long days, plant stress, or natural maturity. Growing during cooler weather helps delay bolting.

Why does my arugula taste bitter?

Arugula naturally has a peppery flavour, but older leaves, hot weather, and drought stress can make the taste stronger and more bitter.

Can you harvest arugula more than once?

Yes. Harvest outer leaves while leaving the central growing point intact. Healthy plants can produce additional leaves for subsequent harvests.

How often should I plant arugula?

For continuous harvests, sow small amounts every 10–14 days while growing conditions remain suitable.

Can arugula grow during summer?

Yes, but hot weather often causes faster bolting and stronger-flavoured leaves. Afternoon shade and consistent watering can help, although spring and autumn are usually better growing seasons.

Is arugula the same as rocket?

Yes. Arugula is also commonly known as rocket or salad rocket.

Can you eat arugula flowers?

Yes. Flowers from properly identified, untreated culinary arugula plants are edible and have a peppery flavour. They can be used sparingly as garnishes.

Does arugula grow back every year?

Arugula is generally grown as an annual. Plants may occasionally self-sow, but new sowings provide more dependable harvests.

How should I store harvested arugula?

Dry the leaves thoroughly after washing, refrigerate them in a suitable container, and use them within several days for the best quality.

See You in the Garden!