To me, the very word “catalpa” sounds Southern. Like catalpa trees in neat rows lining the long driveway up to the cotton Plantation. Catalpa, magnolia and camellia have a Southern ring to their names.
So what are catalpa trees doing in North Dakota and Minnesota? There are two types of catalpa, appropriately named Northern Catalpa and Southern Catalpa, and they’re beautiful. But before everyone in the northland rushes to the garden center for a catalpa, there are limits to its growing range. But if you are within its adapted region, I promise Northern Catalpa will stop traffic as it catches the eye of motorists driving by.
Here are the characteristics of Northern Catalpa, Catalpa speciosa:
- They are a fascinating tree with huge heart-shaped leaves up to 12 inches long.
- Their flowers are orchid-like, showy and beautiful.
- Flowers are followed by decorative long, brown, bean-like seed pods hanging from the tree, giving the tree the nickname “cigar tree.”
- They grow rapidly.
- Tree shape tends to be interesting and informal as the tree ages.
- The most common height in our region is less than 30 feet, putting it in the medium or medium-small tree category. However they can get larger. The record largest catalpa in North Dakota is in Wahpeton, and is 54 feet high with a crown spread of 31 feet. Most do not get that tall.
What is its hardiness range, and where can it be grown?
- It’s considered winter-hardy in zone 4, but zone 4 covers a wide north-south area. North Dakota State University recommends Northern Catalpa for the Southeast quadrant of North Dakota. University of Minnesota recommends the tree be restricted to the southern two-thirds of the state, and used with caution elsewhere.
- Outside these recommended boundaries, Northern catalpa can be used with caution. Choose a protected “micro-climate” within established yards.
What is its best use?
- Its best use is as a featured specimen tree, where it can be viewed and appreciated up close in a visible spot.
- Because its growth habit is sometimes free-form, it might not be the best choice for a boulevard tree.
- The longevity of catalpa is considered short, which is typical of fast-growing tree species. Plant it where you can enjoy it, and don’t feel badly if it only lasts 30 years. There are exceptions, as some individual catalpas have lived much longer.
- Plant it in a “disposable” location, where you won’t feel badly if the tree doesn’t survive forever. If you want to depend on a long-lived tree in a particular location, plant bur oak, but enjoy catalpa where appropriate.