Growing Forsythias in the Home Landscape

After a long, drab winter, most gardeners anxiously await the arrival of spring. One sure sign that spring has truly arrived is the bright yellow flowers of the forsythia (Forsythia x intermedia). Named after William Forsyth, an 18th-century Scottish horticulturist, the forsythia is a deciduous shrub native to China, Korea, and Europe.


Growing Conditions  |  Uses Cultivars  |  Planting  |  Care  |  Pruning  |  Forcing  |   Propagation  |  Problems  |  FAQs  |  More Information


forsythia shrubs in bloom by Volodymyr AdobeStock
Forsythia blooms in bright yellow flowers in early spring. Photo by Volodymyr/AdobeStock

In Iowa, forsythias typically bloom in early to mid-April. The four-petaled flowers vary from light yellow to bright golden yellow and persist for 10 to 14 days. Flowers are produced in groups or clusters along the stems and emerge before the leaves. Forsythias bloom only on the previous year's growth (old wood).

Leaves emerge shortly after flowering. Forsythia leaves are medium to dark green in summer. Fall leaf color is usually poor. Occasionally, however, leaves may turn pale yellow to reddish-purple in fall. Forsythias are one of the last deciduous shrubs to drop their leaves in fall. In Iowa, leaf drop typically occurs in late October or early November.

Forsythias are fast-growing shrubs. Many cultivars (varieties) have spreading, arching growth habits and can reach 8 to 10 feet.

Growing Conditions

Forsythias grow and bloom best in full sun. They will grow in partial shade but won't bloom as heavily. Forsythias adapt to a wide range of soils. However, they do not perform well in wet, poorly drained sites. Forsythias do not have serious insect or disease pests.

Using Forsythias in the Landscape

The forsythia is an excellent plant for mixed shrub borders. It can also be massed on sunny slopes or utilized as an informal hedge. Low-growing cultivars can be used as groundcovers.  Because of their early bloom and their lack of interest in other seasons, these shrubs are well-suited for the middle or back of the border.  They take center stage early in the growing season and can serve as a nice green backdrop for other perennials and shrubs for the remainder of the year.

forsythia blooms by Volodymyr AdobeStock
Forsythia flowers up close. Photo by Volodymyr/AdobeStock

Recommended Cultivars

When selecting a forsythia, choose a cultivar that reliably blooms in Iowa. The flower buds on some cultivars are not reliably cold hardy in Iowa. For example, the flower buds on 'Lynwood Gold' and 'Spring Glory' are hardy to -10°F. Since most parts of Iowa experience winter temperatures below -10°F, these cultivars often don't bloom well in the state.

An excellent forsythia for Iowa is 'Meadowlark.' Jointly introduced by North Dakota State and South Dakota State Universities, in collaboration with the Arnold Arboretum, 'Meadowlark' will bloom after exposure to temperatures down to -30°F. The flowers are bright yellow. 'Meadowlark' is a vigorous, rapidly growing shrub. Its height and width are 8 to 10 feet. 'Meadowlark' has a spreading, arching form.

'Northern Sun' is another good choice for the upper Midwest. Introduced by the University of Minnesota, 'Northern Sun' will flower after temperatures drop to -30°F. The spreading, arching shrub grows 8 to 10 feet tall and has a similar spread. The flowers are yellow gold.

Introduced by Iowa State University, 'Sunrise' is an excellent cultivar for southern and central Iowa. Its flower buds are hardy to -20°F. Plants are covered with small, medium yellow flowers in early spring. 'Sunrise' is a semi-spreading, compact shrub with a mature height and width of 5 feet. Its compact size makes 'Sunrise' ideal for small hedges or shrub borders.

Another hardy forsythia variety is 'Northern Gold.' A Canadian introduction, 'Northern Gold' is an upright shrub that grows 6 to 8 feet tall. Flowers are golden yellow.

Other forsythia cultivars that bloom well in Iowa include 'New Hampshire Gold,' and 'Vermont Sun.'

Low-Growing Cultivars

While most forsythia cultivars are grown for their attractive yellow flowers, a few are grown for other features. 'Bronxensis' is a low-growing cultivar often used as a groundcover. Plants commonly grow 18 to 24 inches tall. Unless covered by snow, 'Bronxensis' doesn't usually bloom well in Iowa as its flower buds are hardy to -10°F.
Gold Tide® is another low-growing forsythia. The compact, spreading plant grows 2 to 3 feet tall. Its flower buds are hardy to -15°F. Gold Tide® is commonly used as a groundcover and foundation planting.
'Fiesta' is a compact shrub with variegated foliage. Plants typically grow 3 to 4 feet tall. Leaves are green with yellow centers.

Spring Garden Magnolia Forsythia
This yellow-blooming forsythia is a good spring-blooming addition to the back of the garden border.

Planting & Care

Planting

Forsythias are readily planted in spring (April - early May) as well as in late summer/fall (August through early November).  The most common way to find forsythia in the home landscape is to purchase container-grown plants from the garden center or as bare root from mail-order nurseries.

To plant container-grown shrubs, dig a hole 2 to 3 times wider than the diameter of the container. The depth of the hole should be the height of the root ball. Slope the sides so the top of the hole is several inches wider than the bottom. Once the hole has been prepared, fap the sides of the container to loosen the soil ball from the container, then slide the shrub out of its container. If the sides of the soil ball are a mass of roots, shave the outer 1/2 inch of soil off the root ball with a sharp knife or spade. The goal is to remove any roots circling the root ball and leave behind roots pointed straight out from the root ball.  Carefully place the shrub in the hole. The top of the soil ball should be at the same grade as the surrounding soil. Gradually fill the hole with soil and firm it around the root ball with your hands. Do not add compost, peat, or other organic materials to the soil.  Once planted, water thoroughly. Learn more about planting in this video: Gardening in the Zone: Planting Shrubs.

Planting bare root plants happens in the spring.  Plant them as soon as possible after they arrive before spring growth begins.  More about planting bare root shrubs can be found in this article: How to Plant Bare Root Plants.

Care for newly planted shrubs like forsythia looks much like the care of a newly planted tree.  Learn more in this article: Care of Newly-Planted Trees.

Care

Forsythias are easy to grow but do require some maintenance. Plants benefit from a layer of mulch at the base to reduce weed growth and retain soil moisture.  Refresh the mulch layer in the spring, if needed.  Supplemental irrigation of established plants is only needed in times of extreme dryness. It is generally not necessary to fertilize healthy, vigorous trees and shrubs in the home landscape.  Most landscape soils in Iowa contain adequate levels of nutrients for trees and shrubs.  Plus, trees and shrubs that are growing in lawns that are fertilized regularly are already being fertilized. 

Pruning

Pruning is the most important chore. Proper pruning produces healthy, vigorous, heavily blooming shrubs. Since they bloom on old wood, forsythias should be pruned immediately after flowering. Pruning the shrubs from mid-summer to late winter will drastically reduce flowering in spring.

When pruning mature forsythias, it's best to remove one-fourth to one-third of the oldest (largest) stems at ground level every other year. New shoots will emerge from the ground and bloom in the following years.  Learn more about pruning shrubs in this publication: Pruning Ornamental Shrubs.

Old, neglected forsythias can be rejuvenated by pruning them back to within 3 to 4 inches of the ground in late winter or early spring. The rejuvenated shrubs will grow back quickly and should begin blooming again in 1 or 2 years.  Learn more about pruning overgrown shrubs in this article: Pruning Large, Overgrown Shrubs.

forsythia in bloom
Forsythia in bloom.

Forcing Branches

Forsythia makes an excellent candidate for forcing branches indoors in early spring.  This process brings branches into bloom indoors several weeks before blooming out in the garden. Learn more in this article: How to Force Branches of Spring-Flowering Trees and Shrubs.

Propagation

Forsythia can be easily propagated using several different methods.  Which you choose will depend on available materials, time of year, time required to propagate, and comfort level with the procedure.  Listed below are the various methods that can be used to successfully propagate forsythia with links to more information about the process.

  • Softwood Cuttings - Taken late May through early July from the current season’s growth.
  • Semi-hardwood Cuttings - Taken mid-July to early fall from the matured current season’s growth.
  • Simple Layering -  Formed by pinning and/or burying a portion of the stem, waiting for new roots to form, and then cutting it from the parent plant.

Potential Problems

Overall, forsythia has few issues.  It does not have notable pest or disease issues in Iowa.  Despite its trouble-free nature, issues still arise from time to time.

Poor Bloom with Vigorous Growth

Forsythias bloom on old wood. Unfortunately, the flower buds on some varieties are not reliably cold-hardy in Iowa. For example, the flower buds on 'Lynwood Gold' and 'Spring Glory' are hardy to minus 10 degrees Fahrenheit.  Since most areas in Iowa experience winter temperatures below minus 10 degrees Fahrenheit, these cultivars often don't bloom well in the state.

Improper pruning is another possible cause. Flower buds on forsythias begin to develop by early summer.  Pruning the shrubs anytime from mid-summer until just before bloom will drastically reduce flowering. To achieve the best floral display, forsythias should be pruned immediately after flowering.

Blooms Only on the Lower Branches

When selecting a forsythia, choose a variety (cultivar) that blooms reliably in Iowa.  The flower buds on some varieties are not reliably cold hardy in Iowa.  For example, the flower buds on 'Lynwood Gold' and 'Spring Glory' are hardy to -10 degrees Fahrenheit.  Since most parts of Iowa experience winter temperatures below -10 degrees Fahrenheit, these cultivars often don't bloom well in the state.  Most likely, you have a variety that is not reliably cold-hardy in Iowa.  The lower branches bloomed because they were covered with snow and protected from the cold winter temperatures. 

Excellent forsythia varieties for Iowa include 'Meadowlark' (8 to 10 feet tall), 'Northern Sun' (8 to 10 feet tall), and 'Sunrise' (5 to 6 feet tall).  All three varieties possess excellent flower bud hardiness and bloom reliably in Iowa.


Forsythia hedge
Forsythia maintained as a hedge.

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Last reviewed:
March 2024