Border forsythia
Forsythia x intermedia
Border forsythia (Forsythia x intermedia) is a shrub suited to the Colorado Front Range. It matures to about 6 to 10 ft tall and 6 to 10 ft wide, fast-growing, needs medium water, and prefers full sun. Flower buds often kill in our late spring frosts, many years it blooms only on the lower stems sheltered by snow.
On the CSU listmedium water6 to 10 ft tall and 6 to 10 ft wide
Photos
- Photo 1: (c) David Dyck, some rights reserved (CC BY)
- Photo 2: (c) Ana Ka'ahanui, some rights reserved (CC BY)
- Photo 3: (c) Dr. Boli, some rights reserved (CC BY)
At a glance
Will it survive here?
- Hardiness zones
- USDA 4 to 8
- Water needs
- medium water
- Sun
- Best in full sun.
- Soil
- clay, loam
- Soil pH
- 6.0 to 7.5
- Hail tolerance
- moderate
- Wind tolerance
- moderate
- Salt tolerance
- low
How big, what shape?
- Mature size
- 6 to 10 ft tall and 6 to 10 ft wide
- Planting spacing
- ~10 ft apart (7 ft for a hedge/screen)
- Growth rate
- Fast
What it looks like, and when
- Bloom time
- early spring
- Bloom color
- yellow
- Bloom length
- 2 to 3 weeks
- Foliage
- Deciduous
Who else benefits
- Pollinator value
- low
- Deer
- Not rated
- Colorado native
- No
Also worth knowing
- Fire rating
- Not rated
Things to know before you plant
- Spreads aggressivelyBranches root where they touch ground; expands clump steadily
Frequently asked questions
- Is Border forsythia good for the Colorado Front Range?
- Yes, Border forsythia is a well-suited shrub for Colorado's Front Range.
- What should I know before planting Border forsythia?
- The main things to know: Branches root where they touch ground; expands clump steadily
- How big does Border forsythia get?
- It matures to about 6 to 10 ft tall and 6 to 10 ft wide.
- How far apart do I plant Border forsythia?
- Space Border forsythia about 10 ft apart for a full, natural form, or about 7 ft apart for a faster hedge or screen.
- Is Border forsythia hardy on the Front Range?
- Border forsythia is hardy in USDA 4 to 8. The Colorado Front Range spans roughly USDA 4b to 6a, so it is well within range.
- How much water does Border forsythia need?
- It needs medium water once established.
- How fast does Border forsythia grow?
- Border forsythia is a fast-growing shrub. Growth rate depends on water and site conditions on the Front Range.
- Is Border forsythia native to Colorado?
- No. It is not a Colorado native, but it grows well on the Front Range.
- How long does Border forsythia bloom?
- Border forsythia blooms for about two to three weeks on the Front Range. Bloom timing shifts a week or two with elevation and spring weather.
