Knowledgebase
flowering shrub #744383
Asked April 14, 2021, 6:37 PM EDT
Larimer County Colorado
Expert Response
Hi, and thank you for your question. First I would say, don't take out that Rose of Sharon until you are sure that it didn't survive the winter. Since they are late summer bloomers (July-August), Rose of Sharon are late to wake up in the spring, as well. I haven't walked to the back of my yard lately to look at mine, but they probably still look dead, as well. Take your pruners and snip a little bit off the ends of a couple of the branches to check and see if you find live wood. Live wood will look fresh and have a little greenish hue, and will be more difficult to cut or snap off. If you can't snap it off easily, it is probably alive. Secondly, I would encourage you to make sure that your trees and shrubs are getting water in the winter when we have not had natural precipitation (rain or snow for about 3 weeks). Give your trees and shrubs some supplemental water on days when the temperature is above freezing, and the ground is not frozen and you can apply the water to soak in before dark. Newly planted shrubs require more water than established shrubs that have been planted for at least one year. The following recommendations assume shrubs are mulched to retain moisture. In dry winters, all shrubs benefit from winter watering from October through March. Apply 5 gallons two times per month for a newly planted shrub. Small established shrubs (less than 3 feet tall) should receive 5 gallons monthly. Large established shrubs (more than 6 feet) require 18 gallons on a monthly basis. Decrease amounts to account for precipitation. Water within the dripline of the shrub and around the base. Here is a link to a Fact Sheet about winter watering: https://extension.colostate.edu/topic-areas/yard-garden/fall-and-winter-watering-7-211/
So, we hope that your Rose of Sharon is not dead. However, if it is dead, or if it is still alive and you want to add other shrubs in that unprotected spot, an evergreen might not be the best choice, as our freeze-dried winters can be hard on some evergreens in unprotected spots. I think that your choice of Rose of Sharon (Hibiscus syriacus) is a good one, so if it is dead, you could replace it and be sure to winter-water according to the directions above. But, be aware that Rose of Sharon can grow to 12' tall, as well. A red-twig dogwood (Cornus sericea) would also be a good choice, for the winter interest of the red-stems, as well as flowers (although not showy)in May, and interesting fruit after the flowers. A cultivar such as 'Isanti' would stay down around 5'-6' in height.
There are some viburnums that would fit your requirements, for example: 'Mini-man' Viburnum (Viburnum burejaeticum 'Mini-man') tolerates dry, full-sun conditions, flowers in mid-spring, followed by black berries, and grows 3'-6' tall. Compact European cranberry (Viburnum opulus 'Compactum' ) grows to a height of 4'-6', will grow in full sun to part shade, has creamy-white spring flowers, followed by red fruit, and purplish-red fall color.
Also, you could always consider a nice lilac (Syringa sp.) for that area. While they don't provide year-round interest, there are those wonderful sweet-smelling flowers in spring, which range from deep lilac to pink to variegations, they love full sun and are drought tolerant once established. The Korean lilacs (Syringa meyeri 'Palabin' and Syringa patula 'Miss Kim') will be smaller in height (5'-8') and 4'-6') respectively.
Here is a link to a Fact Sheet about native shrubs for Colorado, in case you are interested in growing a native shrub. You would want to check the charts for small to medium-sized shrubs.
https://extension.colostate.edu/topic-areas/yard-garden/native-shrubs-for-colorado-landscapes-7-422/
Best of luck with choosing a new shrub, and be aware also, that you can always send an email to <personal data hidden>. That email inbox is monitored and responded to by Larimer County master gardeners everyday.