Newsletter Articles
Invasive Plants to Avoid in Southern California
Yes, several popular garden plants are invasive in Southern California and worth avoiding, including highway iceplant, pampas grass, English ivy, and Spanish broom. The good news: California lilac (Ceanothus) is not one of them. It is a California native and a great plant to grow instead. Below are the invasive ornamentals to skip and the natives to plant in their place.[1]
Quick answer: Avoid the worst invaders rated by the California Invasive Plant Council (Cal-IPC), such as iceplant, pampas grass, English ivy, and Spanish broom. Butterfly bush is a lower-concern watch species here. California lilac (Ceanothus) is a native, not an invasive, so plant it and other natives like California fuchsia instead.
What Is an Invasive Species?
An invasive plant is one that escapes the garden, spreads on its own into wild areas, and crowds out native plants and the wildlife that depend on them. The California Invasive Plant Council (Cal-IPC) keeps the authoritative inventory for our state and rates each listed plant High, Moderate, or Limited based on its ecological impact and how aggressively it spreads; a separate Watch flag marks plants of emerging concern.[2]
Invasive Plants to Avoid in Southern California
These common landscape plants are on the Cal-IPC inventory and are best left out of a SoCal garden:
| Plant | Cal-IPC rating | Why avoid it |
|---|---|---|
| Highway iceplant (Carpobrotus edulis) | High | Smothers coastal and dune habitat |
| Pampas grass (Cortaderia selloana) | High | Windblown seed invades open land |
| English ivy (Hedera helix) | High | Blankets ground and trees, smothering natives |
| Spanish broom (Spartium junceum) | High | Takes over slopes and roadsides |
| Green fountain grass (Pennisetum setaceum) | Moderate | Seeds into wildland and burns readily |
| Periwinkle (Vinca major) | Moderate | Spreads into shady creek areas |
| Mexican feather grass (Stipa tenuissima) | Limited | Reseeds freely into wild areas |
| Butterfly bush (Buddleja davidii) | Watch | Lower concern in CA; a known invader farther north |
The four High-rated plants, iceplant, pampas grass, English ivy, and Spanish broom, are the ones to avoid most firmly, since they do the most damage to California wildlands.[1][3][4]
The Moderate-rated fountain grass and periwinkle, and Mexican feather grass, are also worth keeping out of the garden, especially near open space.[5][6][7]
Is Butterfly Bush Invasive in California?
Butterfly bush (Buddleja davidii) is a lower-concern Watch species in California, not one of the High-rated escapees. It is a proven invader in the Pacific Northwest, so caution is still warranted, and it spreads by seed. If you love it for pollinators, look for a sterile or seedless cultivar, or better yet plant a native pollinator shrub instead.[8]
Is California Lilac Invasive?
No. California lilac is the common name for Ceanothus, a genus of shrubs native to California, and it is not an invasive plant; it does not appear on the Cal-IPC inventory. In fact it is one of the best native shrubs you can plant, prized for its clouds of blue spring flowers and its value to pollinators.[9]
Two quick clarifications. First, do not confuse California lilac (Ceanothus, a native) with common lilac (Syringa), a non-native ornamental; neither is on California’s invasive lists. Second, on the question of whether its roots are invasive: Ceanothus is a well-behaved shrub with no reputation for aggressive or damaging roots. Its one quirk is that it is drought-adapted and tends to be short-lived if given regular summer water once established, so the real care tip is to water it sparingly.[9] You can browse California lilac at Green Thumb Nursery.
Plant These Instead: Native and Non-Invasive Alternatives
For every invasive plant there is a better-behaved option, and many are California natives that support local pollinators and birds:[10]
| Instead of this invasive | Plant this |
|---|---|
| Pampas grass / fountain grass / Mexican feather grass | Deer grass (Muhlenbergia rigens), California fescue, or blue grama |
| Iceplant groundcover | Low Ceanothus (California lilac) or bearberry manzanita |
| Butterfly bush | California fuchsia or another native pollinator shrub |
| English ivy | Native groundcovers and manzanitas |
California fuchsia is a standout native for drawing in hummingbirds, and California lilac makes a gorgeous flowering backdrop or informal hedge. Our team can help you find natives suited to your yard.
Stop by any Green Thumb Nursery location and we will help you swap out an invasive plant for a beautiful California native that belongs here.
Invasive Plant FAQ
Is California lilac invasive?
No. California lilac (Ceanothus) is a California native shrub, not an invasive plant, and it is not on the Cal-IPC inventory. It is actually a recommended native for its blue spring flowers and pollinator value.[9]
Are California lilac roots invasive?
No. Ceanothus is not known for aggressive or damaging roots. Its main quirk is that it is drought-adapted and can be short-lived if given regular summer water, so water it sparingly once established.[9]
Is butterfly bush invasive in California?
Butterfly bush (Buddleja davidii) is a lower-concern Watch species in California, not a High-rated invasive, though it is a known invader in the Pacific Northwest. Choose a sterile cultivar or a native pollinator shrub to be safe.[8]
What are the worst invasive plants in Southern California?
Among garden plants, the High-rated invaders to avoid include highway iceplant, pampas grass, English ivy, and Spanish broom, all on the Cal-IPC inventory.[1]
What can I plant instead of invasive plants?
Swap in California natives: deer grass for ornamental grasses, low Ceanothus or manzanita for iceplant, and California fuchsia for butterfly bush.[10]
Sources
- [1] Cal-IPC, Carpobrotus edulis (highway iceplant) profile: cal-ipc.org
- [2] Cal-IPC, Cortaderia selloana (pampas grass) profile: cal-ipc.org
- [3] Cal-IPC, Hedera helix (English ivy) profile: cal-ipc.org
- [4] Cal-IPC, Spartium junceum (Spanish broom) profile: cal-ipc.org
- [5] Cal-IPC, Pennisetum setaceum (green fountain grass) profile: cal-ipc.org
- [6] Cal-IPC, Vinca major (periwinkle) profile: cal-ipc.org
- [7] Cal-IPC, Stipa tenuissima (Mexican feather grass) profile: cal-ipc.org
- [8] Cal-IPC, Buddleja davidii (butterfly bush) profile: cal-ipc.org
- [9] Calscape (CNPS), Ceanothus thyrsiflorus (blueblossom / California lilac): calscape.org
- [10] PlantRight, Better Plants (native alternatives): plantright.org
Written by Kelsey W.
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