When to Plant Arugula in Alaska (2026 Guide)

Arugula is a fantastic addition to any Alaskan garden, especially given its preference for cooler growing conditions. This peppery salad green can be planted multiple times throughout the growing season, providing fresh greens from spring through fall. With the last spring frost occurring on May 26 in Zone 5a, you can get a head-start on your garden as soon as the soil can be worked.

For those in Alaska, understanding the right planting times is crucial due to the relatively short frost-free season of about 107 days. Arugula typically matures in just 40 days, making it an ideal crop for quick harvests. By planting in succession, you can enjoy a continuous supply of fresh arugula from April through June, with a second planting in late summer for fall greens.

Make sure to keep an eye on this fast-growing crop, as it can bolt quickly in warmer temperatures. If you want to extend your harvest, consider intercropping arugula with slower-maturing plants. Remember, the first fall frost around September 10 means you'll want to have your second round of arugula harvested before then.

Planting Schedule by USDA Zone in Alaska

Zone	Indoor start	Transplant out	Direct sow	Harvest
Zone 5a	Start March 15 – March 31, ~8 weeks before May 26	Transplant outdoors May 15 – May 26, after last frost	Direct sow May 15 – June 15, after last frost	Harvest from June 25 – July 31

Arugula Planting Windows in Alaska

Indoor start: Start arugula indoors between March 15 and March 31 to ensure a head start before outdoor planting.
Transplant outdoors: Transplant arugula outdoors from May 15 to May 26, right after the last spring frost.
Harvest: Begin harvesting arugula from June 25 until July 31 for the best flavor and tenderness.

Common Mistakes Growing Arugula in Alaska

One common mistake in Alaska is planting arugula too late, especially with the rapid onset of summer heat. If you're not careful, your crop might bolt before you even get a chance to harvest it.
Many gardeners in Alaska assume that since arugula is a cool-weather crop, it can be sown in the fall without concern. However, the likelihood of early frost can jeopardize your harvest if the plants are not adequately prepared.
Over-watering is another pitfall for Alaskan gardeners. The cool climate may lead to misconceptions about water needs, but consistent moisture is important for healthy arugula growth. Be careful not to drown your plants with excess water.
Alaska's fluctuating temperatures can be tricky for new gardeners. Late spring snowfalls are not uncommon and can damage tender seedlings. Always have a plan to protect young plants should unexpected weather strikes.
Another mistake is not utilizing succession planting adequately. In Alaska, it's easy to miss windows where growing conditions are optimal. By staggered sowing every few weeks, you can enjoy fresh arugula through the growing season.

Frequently Asked Questions

What if I'm in a cold pocket of Alaska?

If your garden is in a cold pocket, you can still successfully grow arugula by starting seeds indoors and using cloches or row covers for protection. Just remember to wait until the risk of frost has passed before transplanting.

Can I still plant arugula in May?

Yes, you can plant arugula in May in Alaska, especially after the last frost date of May 26. Just ensure that you monitor weather forecasts for potential late frosts and cover your new plants if necessary.

Is it necessary to water arugula frequently?

While arugula prefers consistent moisture, it's important not to overwater. Water your plants every few days, especially during dry spells, and check the soil for moisture to ensure optimal growth.

When is the best time to harvest arugula?

The best time to harvest arugula is when leaves reach 3–4 inches in height. This typically occurs between June 25 and July 31 in Zone 5a. Always pick the outer leaves to encourage further growth of the plant.

What pests should I watch for with arugula?

Flea beetles are a common pest for arugula in Alaska. Look for tiny holes on the leaves, which indicate damage. Use floating row covers at planting to protect against infestations and remove them at bolting time for airflow.