Forsythia: How to Grow Forsythia
You can tell for certain that spring has finally come when you see the bright yellow blossoms of the forsythia plant start to open up their petals. Often beginning to bloom during the tail end of winter, there's nothing like the mesmerizing sight of golden forsythia flowers peeking from powdery white snow to signal the arrival of warmer days.
Forsythias can be great picturesque additions to your landscape. And although this eye-catching shrub is generally easy to look after, you have to put in extra care to make sure their blooms reach their highest potential. Keep reading to know more about forsythia shrub care and growing tips.
Forsythia, also commonly known as Golden Bell, is a genus of deciduous flowering plants that belong in the olive family Oleaceae. The shrub is popular for its brilliant yellow flowers that bloom just after winter, earning it the nickname Easter Tree due to its being a symbol for the coming spring.
Forsythias are often found in gardens and parks due to their captivating springtime presence and easy-to-care-for nature. Its versatile form allows it to be a convenient landscape tool that can either serve as a singular focal point or a hedge. Aside from its aesthetic purpose, it is also usually grown as a privacy screen around a property.
This deciduous shrub also plays a role in traditional Chinese herbology. Forsythia fruits have long been used as a fundamental medicinal herb that is believed to help treat various symptoms and ailments.
Facts About Forsythia
The genus Forsythia is documented to include about 11 species, most of which originated from eastern Asia and one being native to southeastern Europe.
The first species to be discovered by a western researcher was the Syringa suspensa. A student of Carolus Linnaeus, Carl Peter Thunberg collected the specimen from China during the early 18th century. It was then reclassified to the genus Forsythia in 1804, which was named in memory of Scottish horticulturist William Forsyth. He was a founding member of the Royal Horticultural Society and a royal head gardener.
One of the best things about forsythia is its fast-growing and mostly low maintenance nature. Forsythias are commonly disease-free and are hardy enough to tolerate drought conditions and even severe neglect.
Although they require little to no care, forsythias thrive best when planted in well-draining soil and placed in an area with direct sun exposure. Beginners often make the mistake of spacing the shrubs too closely together, which could negatively impact its growth and appearance. It's best to give it ample space to grow since its branches can spread out widely if not pruned.
Forsythias are notable for their magnificent arching branches that can reach great heights. At maturity, a forsythia can grow up to 8 to 10 feet (2.4 to 3 meters) in height and reach a horizontal spread of 10 to 12 feet (3 to 3.7 meters). It spreads out in a majestic fountain-like manner.
Forsythia shrubs grow at a rapid rate, with their height increasing by more than 24 inches (60 centimeters) yearly. It is not uncommon for forsythias to double or even triple in size in a short span of time. Due to its tendency to be invasive, one plant can easily grow into several in a few years if not pruned or maintained.
Dotting the branches of the forsythia shrub are medium to dark green leaves, with each leaf arranged opposite another along the cane. Although the leaves are usually simple rather than compound in growth, there are rare instances where it consists of three leaflets instead of just one.
The length of the leaves can range between 1 to 4 inches (2.5 to 10 centimeters) and are either serrated or smooth. Leaf buds usually begin to open as flowers start to fade after their seasonal blooming.
Forsythia flowers normally bloom in the early spring, right before new leaves are produced. Much like other plants that produce flowers during springtime, forsythia blossoms grow from one-year-old wood, and flower buds begin developing during the summer and fall of the previous year.
The flowers are characterized by their bright yellow hue and consist of four to five petals connected at the base. The petals are often so thick that it can thoroughly cover the branches, giving the shrub a completely golden look, especially when viewed from afar.
Forsythias consist of hard, dry, brown fruits that can be split open into two separate chambers. Each chamber houses multiple winged seeds. The fruits are about ¼ inch (0.60 centimeter) long and develop from pollinated flowers.
Aside from the slight variations in sizes and length of the blooming period, there aren’t that many noticeable distinctions among the several varieties of forsythia. They all share the same signature color yellow, albeit with subtle differences in shade.
Forsythia x intermedia, also known as border forsythia, is a cross between Forsythia suspensa and Forsythia viridissima. This particular hybrid has produced many new cultivars that have grown popular today.
Here are some of the most well-known types of forsythias:
Forsythia x intermedia 'Sunrise'
Introduced by Iowa State University, Sunrise is a type of forsythia that can grow up to 5 feet (1.5 meters) tall and wide when mature. Its semi-spreading behavior and the multitude of branches make it look full and compact.
Its bright yellow blossoms may be smaller compared to other varieties, but the large number of flowers composing each branch gives it a fuller look that results in a vibrant burst of colors. It is also said that its petals can withstand temperatures as low as -20°F (-29°C).
While its leaves are normally medium green, they become tinted with a slight purple hue during the fall when temperatures are cool and dry. If a small hedge is what you’re aiming for, then the dense appearance of Sunrise forsythia may be perfect for the job.
Forsythia x intermedia 'Kolgold'
Kolgold, or more commonly known for its trade name Magical Gold, is most prominently recognized for its relatively larger flowers that are at least an inch in width. It is normally around 4 to 5 feet (1.2 to 1.5 meters) in height and has a habit of blooming from bottom to top.
Forsythia x ‘Meadowlark’
Meadowlark is a cultivar made known by the South Dakota State University, North Dakota State University, and the Arnold Arboretum in 1986. It’s a hybrid of Forsythia ovata, a variety native to Korea, and Forsythia europaea, native to Europe. The largest Meadowlark shrub documented in North Dakota was 13 feet (4 meters) tall with a 15 feet (4.5 meters) spread.
The most noteworthy feature of the Meadowlark is its severe tolerance to drought and below-zero temperatures. The shrub can maintain the ivy green color of its leaves until late fall. If you reside in a place with particularly harsh cold weather, then the Meadowlark forsythia may be right up your alley.
Courtasol, also called Gold Tide, originates from France and is one of the dwarf varieties of forsythia. Typically growing to only 20 inches (50 centimeters), this cultivar is a ground cover type that can spread as much as 4 feet (1.2 meters) wide. It features lemon yellow flowers and medium green leaves that become purplish in the fall.
How to Grow Forsythia
Forsythias grow best in loose and well-draining loam soil, but tougher varieties can also tolerate clay as long as it’s not overly wet or swampy. If you have dry, slightly sandy soil, then you can enrich it by adding in 2 to 3 inches of organic matter into the area to be planted. Putting a layer of mulch can help conserve soil moisture and suppress weeds.
If you have access to a soil testing kit, then it’s best to check your soil’s condition first before jumping right into planting. The ideal pH level for forsythias can range between 6.8 to 7.7. You can use powdered limestone to raise your soil’s pH level if it doesn’t fall in the suitable range while adding ground rock sulfur can help lower it.
Forsythias like to bask in sunlight, so make sure to find a spot that offers the best sun exposure. This shrub requires a daily fix of at least 4 to 6 hours of direct, unfiltered sunlight.
While it may be possible for your forsythia bush to grow in partial shade, doing so can greatly reduce its ability to produce the mass of bright yellow blossoms that it’s primarily known for. So if you wish to have impressive golden foliage by spring, then don’t forget to let your shrub get plenty of sun. You can also improve its growth by regularly thinning out the inner branches to let light in.
Temperature & Humidity
Soil temperature also has a strong impact on a forsythia’s flowering ability. It performs best when the temperature is around 55°F to 70°F (13°C to 21°C), but some varieties are able to survive in colder conditions. If the temperature becomes too cold during the winter, the forsythia could have fewer flower buds come springtime.
In terms of air moisture, forsythia shrubs prefer slightly humid climates. Arid climates might lead to a decline in the number of blossoms produced, while too much moisture in the air could result in wilting.
For a forsythia to grow into its peak condition, it needs to be maintained in moderately moist soil. This can be achieved through regular watering, ideally with at least 2 inches (5 centimeters) of water per week. However, some forsythias are hardy enough to handle some drought.
Younger plants, in particular, need more careful attention and consistent watering. Once they’ve become mature, you can start cutting back and only water forsythias during long dry periods.
A good way to check if your shrub is getting enough water is to monitor its leaves. If you see the leaves starting to sag down, then this indicates that your shrub needs more moisture. Since forsythia shrubs have shallow roots, you need to supply the water slowly so that it can be properly absorbed by the plant and avoid waterlogging.
Forsythias generally don’t require fertilizer to be healthy, but the added nutrients can certainly help promote better growth. However, you have to wait until the shrub is at least a year old to start adding any fertilizer, especially if it’s already planted in nutrient-rich soil.
A cup of granular fertilizer every two to three months in the spring and summer is more than enough for younger shrubs. However, you have to keep in mind that forsythias should not be fertilized in the fall and winter. Moreover, mature forsythias require even less of these nutrients since they are already resilient enough.
Choosing the right fertilizer is just as important as the frequency of application. An all-purpose fertilizer that contains a suitable balance of potassium, phosphorus, and nitrogen is appropriate for a forsythia’s growth.
When you find that your forsythia bush has overgrown its planting area and no amount of pruning can save it anymore, then you have no choice but to transplant it somewhere else. It’s best to do this in the spring when the shrub has finished flowering, but you can also do it in the fall after the leaves have fallen off. This way, you can have a better view of what you’re doing while moving the plant.
The most challenging yet essential part of transplanting a forsythia is managing its roots. You need to dig a trench that’s at least 20 inches (50 centimeters) in radius around the base of the plant. You might end up cutting into a few roots, but newer ones will grow quickly in spring so you don’t have to worry. Watering the shrub well the night before can help make the soil softer and easier to dig through.
Another important consideration is to find a new area that would be able to accommodate the size of your forsythia bush. You need to confirm which variety it is and find out its possible maximum height and spread upon maturity. Once you’ve secured a good spot for your forsythia, then you can start planting the root ball and care for it like how you normally would with newer plants.
One of the main complaints when it comes to forsythias is its propensity to grow into an unruly shape. Since forsythia shrubs have characteristically fountain-like canes and tend to spread out at a quick rate, pruning is one of the regular activities that you need to do to properly maintain your golden foliage.
You can’t do effective pruning work without preparing the proper tools. For canes that are up to ½ inch (1.2 centimeters), pruning shears are usually the best option for the job. A pruning saw, on the other hand, is a much better tool for cutting slightly thicker branches.
You can start by clipping off the dead or bent branches first, as well as the ones that are growing too close to each other that they begin rubbing against one another. For more mature plants, you need to trim at least ¼ to ⅓ of the oldest and longest canes close to ground level every year to encourage new growth. You can also carefully prune some of the inner branches so it'll open up more and allow better air circulation and more sunlight to filter in.
One important thing to note is that pruning your forsythia into a proper hedge might hinder its flowering potential. So if you wish to have an abundance of golden blooms, then letting your shrub grow naturally with just the most necessary trimming is the best way to go.
The most common way to propagate forsythia shrubs is through cuttings. This is best done during springtime when new growths have started setting. You can find the newly-formed stems on the outermost edges of the shrub.
Start by clipping the tips of the current year’s new stems at 4 to 6 inches (10 to 15 centimeters) and removing the leaves attached to the lower half. Dip the slashed end in rooting hormone and place it in a pot with a hole down the center, filling it with soil.
Cover the potted cutting with plastic wrap or place it inside a sealed plastic bag to keep it from drying out. Make sure to place it in a spot with a warm temperature but avoid direct sunlight. Open the bag after a few days to let fresh air in. In about 6 to 8 weeks, new roots would have formed and you can then begin transplanting the stems to a bigger pot or an area in your garden.
Forsythia Health Benefits
Although forsythias are best known as attractive springtime foliage, these perennial shrubs also offer various health benefits such as antiviral, anti-inflammatory, and antibacterial properties that could aid in treating minor ailments.
A study published in Integrative Biology provides evidence supporting the antiviral capabilities of forsythia. It details how forsythia and Japanese honeysuckle boosts immune function and mitigates the growth of the influenza virus.
Another study, published in the Journal of Ethnopharmacology, shows the anti-inflammatory effects of Forsythia suspensa against ulcerative colitis. The researchers concluded that forsythia has potential in treating intestinal inflammation.
In a study conducted in 2017, researchers were able to discover that dried forsythia fruits can help combat bacteria such as streptococcus, staphylococcus aureus, E.coli, and others.
Uses of Chrysanthemum
The fruits of the forsythia plant, called Lian Qiao, are widely used in traditional Chinese medicine as a medicinal herb. It is used to help treat symptoms such as sore throat, inflammation, nausea, and fever.
The dried fruits are often taken as a tincture or powder. Dosage can differ from person to person so it’s best to consult a Traditional Chinese Medicine practitioner before using it as a treatment. In order to maximize its effects, forsythia is usually paired with honeysuckle and other ingredients.
Due to its brilliant splash of color and the fact that it’s an easy plant to care for, forsythia bushes are commonly used for ornamental purposes. It can be planted as a singular attractive centerpiece for your garden or as a wall of hedging to use as a backdrop for other plants.
Its seasonal blooms give it a particular charm, boasting of green foliage during the summer, a delicate shade of red in the fall, and it's signature golden blossoms as early spring approaches.
If you’re looking for a radiant burst of color to add to your garden collection, forsythia shrubs may just be what you need. It requires minimal attention and provides a stunning view whenever spring comes around.
Frequently Asked Questions
Are forsythia flowers edible?
YES, forsythia flowers are edible. Although there is a lack of research studies supporting the safety of forsythia flowers for human consumption, it is widely used in the world of cuisine as a salad garnish. Despite its slightly bitter taste, you can mix in a few pieces of it to add a unique splash of yellow into your salad or soup.
When should forsythia be pruned?
Unless your forsythia bush has become an overgrown mess that needs to be lopped down to the ground, pruning it is something that you can do annually. Younger ones don’t need much trimming, but mature forsythia bushes require extra pruning to maintain a clean form.
If you wish to maximize your forsythia’s blooms, then the most opportune time for you to prune it is during the spring shortly after the flowers have finished blooming. When the blossoms have started fading and leaf buds are beginning to form, you’ll have a better view of the branches so you can comfortably pick out which ones to snip off.
Pruning forsythias can be quite an intimidating task, especially for gardening newbies, but you don’t need to fret too much over making mistakes. Since forsythias are fast-growing bushes, any error you make while pruning can easily be corrected in succeeding years.
How long do forsythias stay in bloom?
Forsythia flowers usually bloom around late March to mid-April. Flower buds often start opening up during the very end of winter and the yellow blossoms are at their peak at the beginning of spring. According to Richard Jauron, a horticulture specialist from Iowa State University Extension, forsythia flowers can stay in bloom for around 10 to 14 days. Not long after that, new leaves will start forming.