Revisiting an Old Favorite

Some memories stick with you no matter how many years have passed. I don’t recall the exact date, but it was early on during the Reagan administration that Mawmaw Lat and Mrs. Vengie Lee Ziegler signed up for a leisure learning home landscaping class at Southeastern in Hammond. This was following the 1970s environmental movement when public interest in plants and landscaping was at an all-time high.

Mawmaw and Mrs. Vengie Lee were always game to learn new things, but on this occasion, I think the impetus for signing up was to develop a landscape plan for my mom’s yard. Mrs. Vengie Lee was a self-trained horticulturist and had the greenest of thumbs. I suppose that’s why she tagged along. I remember riding along to Zuelke’s Nursery in Port Vincent after they completed the class to pick out the plants for mom’s yard.

One plant that both ladies loved was the Althea or Rose of Sharon shrub (Hibiscus syriacus). Of course, these were the old-fashioned varieties that had become a staple of the Southern landscape since they were introduced to the U.S. during colonial times. Altheas quickly became a widely distributed landscape plant, especially across the South. Thomas Jefferson even planted them around his homes.

Like many southern landscape plants borrowed from south central and southeast Asia, Altheas do well in our hot and humid climate. These older varieties were large growing, deciduous shrubs, often reaching 8 to 12 feet in height. However, it has been reported to be invasive in some areas of the country due to the ease with which seeds germinate.

In the 1960s, Dr. Donald Egolf, a renowned shrub breeder at the U.S. National Arboretum, developed varieties with sterile flowers. These preformed just as well, maybe even better, and were slightly shorter in mature height – up to 8 feet. One of these varieties – Aphrodite – was a Louisiana Super Plant selection.

Althea varieties come with either single or double blooming flowers in shades of white, pink, red, and purple. The hibiscus shaped flowers are 3-5 inches wide. With a bloom time from spring to fall, it’s no wonder that Mawmaw and Mrs. Vingie Lee had to have at least 2 or 3 in their yards.

Site requirements for optimal growth include full sun, although some light shade in the late afternoon can be beneficial, and a well-drained soil with pH of 5.5-7.5. That’s about it. Altheas are not fussy plants. The only real issues I’ve seen are when they are planted too deep or in areas where the soil is compacted.

The shrub is typically multitrunked but can be trained to a single trunk tree form. Overall, little pruning is needed as they have an upright growth habit and spread to about 4 to 6 feet wide. Althea is cold hardy throughout the state, but occasionally you will need to prune to remove cold-damaged wood. This is best done in February or March as the plant blooms on new growth.

Plants benefit from an application of slow-release shrub and tree fertilizer in late February or early March. A 3–4-inch layer of mulch over the root zone will help reduce competition from weeds and grass and retain soil moisture. Once established, Althea is a fairly drought tolerant landscape plant and has few pest issues.

There are still a couple of the old-fashioned Altheas growing at Mawmaw’s house that she planted years ago. Unfortunately, we had to replace the ones she planted at my mom’s house after some landscape renovations. We went back with the Aphrodiate variety. I think Mawmaw would approve.

Althea shrub with pink flowers.
5/23/2024 3:51:51 PM
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