We Value Your Privacy

We and our partners use technology such as cookies on our site to personalise content and ads, provide social media features, and analyse our traffic. Click below to consent to the use of this technology across the web. You can change your mind and change your consent choices at anytime by returning to this site.

Update Consent
Loading ...

When to Plant Lupin Seedlings in an Outdoor Garden in Plant Zone 5B?

Updated July 19, 2017

Seeing a field of lupin swaying in an early summer breeze is enough to make anyone want the plant. But you don't need a field to grow this herbaceous perennial. With a bit of knowledge, most northern gardeners can start their own lupins indoors, and transplant them outside in spring.

Loading ...

Seeds and Seedlings

Lupin is easy to start from seed. In U.S. Department of Agriculture plant hardiness zone 5b, it is possible simply to scatter the seed onto the ground in the fall. A more reliable method, however, is to start them indoors in March. Chill the seed in your refrigerator for a week. Nick the tough outer seed coat with a file and soak the seed overnight before planting. Use a lightweight, professional potting mix and start the seeds in small peat pots. Within several weeks, young seedlings will emerge and your lupins are on their way.

Planting Seedlings Outdoors

Although mature lupin prefer cool temperatures, seedlings started indoors have been spoiled by growing in a warm house and are too tender to be planted outside in early spring. Using a cold frame in early April will quickly accustom the young plants to outdoor conditions. Otherwise, in zone 5b, temperatures are conducive for the young seedlings by late April or early May. Keep them evenly moist, but never wet, in this early stage of growth.


Lupin require slightly acidic, well-drained soil and cooler summers. They suffer in heavy clay and in soils that are overly alkaline. Avoid disturbing the roots once the plant is established. Transplanting seedlings is easier if they have been grown in peat pots that can go directly into the ground.

Loading ...

About the Author

Judith Allen has been a writer since 1980. She has contributed to the "Cambridge Encyclopedia of Latin America and the Caribbean," "Brava Magazine" and the "Middleton Times Tribune." Allen has a Master of Arts in history from the University of Wisconsin and is the owner of Eastside Gardens, LLC in Madison, WI.

Loading ...