Saturday, June 16, 2018 1:00 am
Catalpa is a common flowering tree in area
Question: I have noticed a tree with large leaves that is flowering right now. What is it?
Answer: The tree is northern Catalpa. Catalpa is an interesting tree that is related to Trumpet Creeper and Royal Paulownia. Catalpa is a Midwest native fast-growing tree which grows 40 to 60 feet in height, with a narrow, open, irregularly rounded crown and spreading branches. It has large, heart-shaped leaves and large clusters of fragrant, white flowers that usually appear in June or July in northeast Indiana.
Because of its reputation for breaking up in storms due to its weak wood, and the litter caused by the “cigar shaped” bean pods, Catalpa has never really caught on as a landscape tree. Farmers who first came to Indiana and Ohio valued the tree, because the wood of Catalpa was used for fence posts and railroad ties because of its resistance to rot.
The flowers of the catalpa are visited by hummingbirds. It is the sole host of the catalpa sphinx moth, and it provides nutrition for bees in early summer.
The genus name (Catalpa) comes from a North American Indian name.
Catalpa has no serious insect or disease problems. I have seen specimens of catalpa suffer in wet years to verticillium wilt, leaf spots, mildew and twig blight. If you are a fisher person, then you might know that Catalpa worms (the caterpillar of catalpa sphinx moth), make a great bait.
There are a few cultivars of Catalpa in the trades.
• Heartland Catalpa is 50 feet high and 25 feet wide, with an upright, narrow oval habit.
• Pulverulenta has odd speckled variegation on the leaves
• C. x erubescens Purpurea has foliage that emerges purple, and then green later in the season.
Several cultivars of southern Catalpa exist, but are not hardy for our area.
Umbrella Catalpa has a dense, bushy form that is grafted on a regular Catalpa trunk to give it a unique umbrella appearance. This form rarely if ever blossoms. This is truly a tough, time-tested specimen. Hardy to minus 20 degrees maximum
It is easy to propagate Catalpa. Collect the pods after the leaves fall, once the pods are sufficiently dried, but before the seeds have fallen from open pods. Plant the seeds in late fall in a tray used for annuals that is filled with a good professional mix. Plant the seeds about an inch in depth, and place the tray outdoors. Cover the tray with hardware cloth. One should see many seedlings in the spring.
A mature, well-pruned Catalpa tree can be a tree of great beauty, particularly in spring when the foliage is young and the flowers are in bloom.
Unfortunately, it is otherwise a rather coarse tree that many believe does not deserve a prominent place in the landscape. However, many citizens who have a Catalpa tree in their landscape greatly value this native tree.
The Plant Medic, written by Ricky Kemery, appears every other Saturday. Kemery retired as the extension educator for horticulture at the Allen County branch of the Purdue Extension Service.