Forsythia (Forsythia x intermedia) – The Complete Guide

With bright yellow flowers, the forsythia signals the final end of the cold season. Moreover, the lavish flowering shrub has gained a regular place in the ornamental garden, thanks to its undemanding nature.

Planting Forsythia

March opens the ideal time window for planting forsythia. The soil should be completely thawed and there should be no more severe ground frosts to worry about.

Use the following steps to plant your forsythia:

  • Place the still potted young plant in a bucket of water.
  • Dig a planting pit with twice the volume of the root ball.
  • Enrich the excavation with compost, horn shavings, or guano granules.
  • Pot out the forsythia and plant it exactly as deep as in the seed pot.

Press the soil with your hands without compacting the soil too much and water generously. A mulch layer of leaves, lawn clippings or bark mulch proves especially beneficial for the growing phase.

Care Tipps

In order to elicit a forsythia’s golden-yellow floral bloom, you need a well-organized care program. The most important points for the care of forsythia are:

  • Water thoroughly during summer drought.
  • Water container plants regularly when the substrate has dried out.
  • From April to August, fertilize organically every 3-4 weeks with compost or nettle manure.
  • Thoroughly thin out the entire shrub every year in May/June.
  • Cut the plant into shape every 2-3 years immediately after flowering.

Forsythias in containers need winter protection so that the root ball does not freeze through.

If you chose autumn as the time of planting, we recommend in the first winter to pile the young forsythia with leaf soil, straw, or coniferous brushwood. Provide the shoots with a hood of jute or garden fleece.

Established plants bravely face the winter without additional protection.

What Location is Suitable for Forsythia?

Forsythia develops its optimum in a sunny, warm location. However, since the plant has good-natured flexibility, the spring beauty also tolerates a semi-shady or shady location.

Under reduced light conditions, on the other hand, you should expect a somewhat reduced flowering and a loose habit.

The Right Planting Distance for Forsythia

The selected variety and the intended use define the right planting distance. Experience has verified the following values:

  • Varieties with a growth height of 10 ft (3 m): Use a planting distance of 20 inches (50 cm) for pruning hedges and 40 inches (100 cm) for open flowering hedges.
  • Varieties with a growth height of 5 ft (1.5 m): Use a planting distance of 14 inches (35 cm) for pruning hedges and 28 inches (70 cm) for open flowering hedges.

If the forsythia functions as a specimen, try to maintain a distance of at least 50 inches (120 cm) from neighboring plants.

What Soil Does the Forsythia Need?

The forsythia thrives in any good garden soil, which is ideally nutrient-rich and humus-rich. It accepts a low to moderate lime content, as is a slight tendency toward acidic pH.

However, the flowering shrub should not be confronted with waterlogging or soil compaction.

What is the Best Planting Time for Forsythia?

Young plants in containers can be planted throughout the entire growing season. You can create the best starting conditions for a forsythia if you choose early spring as the planting time.

In this case, the ornamental shrub has enough time to establish itself at the site before winter sets in.

When is Flowering Time for Forsythia?

The flowering period extends from early March to late April/early May. On the three-year-old shoots, the flower unfolds in its most beautiful splendor.

If you don’t want to wait that long for your forsythia to bloom, cut off some shoots on December 4 to use them as Saint Barbara branches. Then you can already enjoy the yellow flowers in the vase at Christmas.

Pruning Forsythia Properly

The linchpin of proper care is pruning. The timing plays just as important a role as the pruning itself.

You’ll keep a forsythia in top shape if the flowering shrub undergoes maintenance pruning every 2-3 years. Here’s how to do it right:

  • Prune your forsythia after flowering.
  • Choose a day with dry, overcast weather.
  • Shorten too long shoots by up to two thirds.
  • Place the shears just above a dormant eye.
  • Cut off inwardly directed, crossing and rubbing branches.

Although topiary is only required every few years, thinning takes place each spring. Once the forsythia has faded, cut away all deadwood at the base.

Also, you should make room in the crown for young shoots if older branches threaten to overgrow them. In the end, light and air should reach all regions of forsythia and the shrub should present a harmonious silhouette.

Watering the Forsythia

As a shallow rooter, forsythia quickly suffers from a lack of water during summer drought. If the natural rainfall does not provide enough moisture, you need to water the shrub in time.

In the narrow substrate volume of a container, it is recommended to water the ornamental shrub as soon as the top 1-2 inches (3-5 cm) of the soil has dried.

Fertilizing the Forsythia

The nutrient balance of a forsythia works well in good garden soil without the addition of fertilizer.

If you are out in the garden with a wheelbarrow full of compost anyway, the flowering shrub will gladly accept a portion of the organic fertilizer between April and August.

In the tub, a commercial liquid fertilizer will do the job.


You will rarely have to complain about diseases on a forsythia, if at all. If health problems do occur, they are usually caused by neglect in care.

A weakened shrub is susceptible to fungal and bacterial infections, such as powdery mildew, leaf, and shoot wilt, or Monilia tip drought.

Cut out diseased shoots promptly and put the previous care program to the test. Reaching for chemical pesticides is usually not necessary, as there are plenty of biological control agents available for the hobby garden.


When forsythia is in bloom, most garden pests are still in their starting blocks. The only exception is the shield bugs, as they overwinter as adult insects.

These small, winged parasites resemble aphids. If you control shield bugs when they first appear with the classic soft soap solution, there will be no major damage to this year’s blooms.

Wintering Forsythia

Forsythia is completely hardy as soon as it has rooted itself sufficiently in the bed. Thus, no special protection is required from the second year of standing at the latest.

An exception is made for young plants that are set in the fall, as well as for forsythias in tubs.

Here’s how to overwinter these shrubs properly:

  • Loosely wrap young plants with jute ribbons or garden fleece before the first frost.
  • Pile up the root area with straw, leaf soil, compost, or fir fronds.
  • Wrap the tub thickly with bubble wrap and place it on a block of wood.
  • Cover the substrate with sawdust, wood wool, or leaves.

If the winter comes with bare frost, a shallow-rooted forsythia quickly suffers from drought. If the snow does not show up while the frost dominates, water the ornamental shrub on a frost-free day.

Propagating Forsythia

One of the many likable traits of forsythia is its uncomplicated propagation. If you would like more specimens of the cheerful yellow spring bloomer, you have a choice among these methods:

  • Cuttings: Cut them in July/August, defoliate the lower half and plant them in lean substrate.
  • Saplings: Pull one-year-old shoots to the ground, bury the middle part and let it root until the next year.

Unlike the pure wild species, garden forsythia rarely develops capsule fruits with seeds. Therefore, sowing seeds for offspring is out of the question or requires considerably more effort.

How to Transplant Forsythia Properly?

A forsythia benefits from its natural hardiness when the ornamental shrub is transplanted. In order for the shrub to root quickly in its new location, we recommend this procedure:

  • After flowering, cut back the forsythia by half to two-thirds.
  • Thin out all dead wood, stunted and damaged branches.
  • Cut off excessively long root strands in the radius of the growth height with a spade.
  • With the help of a digging fork, loosen the root ball and lift it out of the ground.

At the new garden site, dig a pit with twice the volume of the root ball. Then, enrich the excavation with compost and horn shavings.

Place the forsythia in the center of the pit and mud the shrub. Do not plant the shrub deeper than in the previous location. Otherwise, it will take 1-2 years before the first flowering after transplanting.

Is Forsythia Poisonous?

Due to its content of saponins and glycosides, forsythia is one of the slightly poisonous plants. Therefore, you should wear gloves during all planting and maintenance activities.

Small children and pets should not be within reach of forsythia without supervision.

My Forsythia Does Not Bloom

If the longed-for blooms fail to appear, the forsythia demonstrates in this way its displeasure at faulty care. These causes for a missing bloom are most common:

  • Pruning in autumn
  • Waterlogging or drought stress
  • Late frost on the ground

Forsythias in containers will fail to bloom if they do not receive protection in the winter. Because of the exposed location of the root ball, it will freeze through in a severe frost.

Subsequent thaws then cause the stressed tissue cells to burst, leaving flower shoots without water and nutrients.

Brown Leaves

Brown leaves on forsythia are considered a symptom of shoot rot. This is a bacterial disease that shows up as brown spots that steadily spread.

As it progresses, foliage and shoots turn dark brown to black. Immediately prune the shrub back to healthy wood.

Yellow Leaves

If the leaves of a forsythia take on a yellow color in mid-season, this pattern of damage indicates Monilia tip drought.

This fungal infection first attacks the flowers and spreads to the foliage as it sprouts on the shrub. In the absence of effective means of control, only radical pruning can save the flowering shrub.

Please burn the cuttings or dispose of them in the household waste to prevent further spread in the garden.