A charming flowering plant associated with springtime, forysthia is among the first to bloom. Its sunny yellow flowers have long signaled the end of winter and symbolized the season of renewal.
Forsythia has also been used in phenology to indicate favorable conditions for planting vegetables, such as peas, onions, and lettuce. Phenology is the study of the relationship between season, climate, and plant and animal cycles. Because plant life adapts to local conditions, the presence of certain plants may signal that the time is right to plant other species.
Originating in Asia and Europe, forsythia is part of the Oleaceae (olive) family and grows to three to 10 feet tall. Because of its height and thick, lush coverage, forsythia is often used to create privacy bushes. Green foliage follows the shrub’s characteristic yellow flowers once the blooms wane.
Growing Conditions for Forsythia
Varieties of forsythia grow in zones four through nine in soil with a pH level of 6.8 to 7.7. Often, forsythia needs only full sun and well-drained soil to thrive. The shrub will also perform in partially shaded environments, but sunlight boosts petal production, and forsythia plants with more sunlight exposure will produce more flowers.
Plant forsythia in early autumn to give its roots time to establish before it falls dormant in late October. If you live in a region that isn’t prone to freezing temperatures, you can plant it year-round. Since different varieties may perform better in different environments, refer to the plant species for specific details.
Spacing is important when planting forsythia in the ground. Consider the plant’s function in your landscape—if your forsythia will be used for privacy, plant them closer together. But always verify the spread of your particular forsythia variety when planning your garden.
You can plant forsythia from a root ball or from cuttings.
Turn the soil and clear it of debris in the soil. If necessary, add compost to particularly dry soil or sand to rich, heavy soil. Dig a hole the same depth of the root ball’s height and double its width. Place the forsythia in the hole at ground level or above. Fill in with soil and pack it gently. Saturate the hole.
As with many shrubs, forsythia will grow from stem cuttings. Cut four-to-six-inch stems of new growth from the outer edges of the plant, and clear the lower three inches of the stems’ leaves. Be sure to use sharp, sterilized shears to preserve the integrity of the stem. Wrap the ends with a damp paper towel and keep them in a dark, opaque plastic bag.
Within 24 hours, place the lower end of the stem in a pot with drainage holes and a mixture of half perlite and half peat moss. Cover it with transparent plastic wrap, and keep an eye out for new growth, which takes anywhere from one month to a growing season. The new plant can go in the ground after the last frost.
Caring for Forsythia
A well-established forsythia requires little watering. During extended dry spells, water the top of the plant rather than the soil in the morning or evening. Take watering cues from the plant’s appearance. If its leaves are wilted and sagging, it’s dehydrated and needs water.
New plants will need a little more attention. Water them regularly. and pour out excess liquid within 10 minutes to prevent an accumulation of moisture.
Pruning a forsythia will boost new growth and increase petal production. Cut back any branches that no longer produce flowers. You may also want to thin out your shrubs. Do this during late winter or spring; if you wait too long to cut back, the new growth may freeze.
Common Pests and Diseases
Although forsythia is generally resistant to pests and diseases, certain infestations may affect your plant’s health.
Aphids are drawn to new growth on the plant and coat the leaves, flowers, and stems with their waste, which can lead to mold. Spraying the plant with water from your hose will usually eliminate the waste.
Houseplant bugs can lay eggs in the plant’s stems. When the bugs hatch, they leave holes in the leaves as they consume the sap. If houseplant bugs infect your plant, ultrafine horticultural oil is an environmentally friendly treatment option.
The two-banded Japanese weevil consumes the edges of forsythia leaves, leaving semicircular indentations behind as evidence of infestation. An acephate spray in August can be effective but is recommended only if the extent of the damage warrants the treatment.
Phomopsis gall, a swelling in the branches brought on by fungus, can infect forsythia plants. Forsythia are vulnerable to the fungus when they are wet and have open wounds. Once phomopsis gall takes hold of forsythia, the plant cannot be treated. Eliminate any infected branches by cutting them four to six inches below the gall. Take care to avoid spreading the spores by disposing of the cut branches in a controlled burn or by double-bagging them in plastic.
It is possible to transmit phomopsis gall with gardening tools. To avoid spreading the fungus when pruning an infected plant, your pruning shears should be sterilized after each contact. Alcohol or a solution one part bleach and 10 parts water is sufficient for disinfecting.
Forsythia is a cheerful reminder of sunshine and springtime, and its easy maintenance makes it a great addition to any garden. Outline a sprawling property line with forsythia for privacy hedging, or plant one in a corner that gets sun all day long.
For tips on DIY spring décor projects using forsythia, read more here.
Ashley Balcazar is a marketing consultant and freelance writer in Denton, Texas. Her work has appeared in The Dallas Morning News and online at CBSDFW.com and Examiner.com. She loves all things art, especially salsa dancing and wordsmithery.
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