Replacing Invasive Plants

On one of my walks here in Southern California I pass a house where they’re removing the English Ivy that thickly carpeted the front landscape. I’m not sure what they’re going to replace it with but it has prompted this article on invasive groundcovers, grasses and shrubs and plants to consider for replacement. Most are native to California so naturally do well in the west.

The following plants are aggressive, grow rapidly and often escape their planned area to make neighbors a tad unhappy. They often have properties that prevent other plants from getting established. Some of this has been taken by the California Invasive Plant Council or Cal-IPC – so thanks to them. I also checked with Joni Clayton, owner of Mockingbird Nurseries in Riverside, on which plants do particularly well in our hot inland. Mockingbird is a great place to get natives and other drought-tolerant plants at very low prices – most sell for $3 a gallon.

For folks in other areas, your state should have a native plant society – or google invasive plants in your states.

GROUNDCOVERS

Instead of:

Iceplant (Carpobrotus edulis), periwinkle (Vinca major), or English Ivy or its relatives Irish or Algerian Ivy

Why? All these form inpenetrable mats that smother other vegetation – and spread widely. Periwinkle, often called vinca, has aggressive trailing stems that root wherever they touch the soil.

Consider:

Mockingbird Nurseries’ Clayton recommends the following, along with a short description:

• San Diego marsh-elder (Iva hayesiana)- fast growing, 1-2’ tall and 4-6’ across
• Trailing Sagebrush (Artemesia Canyon Gray) – 2-3’ but can prune lower
• Low-growing sages, such as low purple sage (Salvia leucophylla P. Sal) – usually under 1’ x 3-4 wide, 1’and Tera Seca black sage (Salvia Tera Seca) – 2’ high by 6’ wide, dark green foliage.

We’ve grown both the salvias and they’ve done very well.

Others to consider include common yarrow, and several low-growing manzanitas and ceanothus. For other California native plants covers that grow a foot or less see this Las Pilitas website

GRASSES

Instead of:

Fountain grass (Pennisetum selacum and all varieties), Pampas grass (Cortaderia selloana, jubata and all varieties) and Mexican Feathergrass ((Nassella or Stipa tenuissima)

Why? Both fountain grass and pampas grass spread aggressively by seed (wind can carry the tiny seeds of pampas grass up to 20 miles!) Both grow very large and take over natural areas, creating serious fire hazards.

Consider:

• California fescue (Festuca californica) – blue-green, 2-3’ tall plus flower stalks
• Blue fescue (Festuca glauca) – native to Europe, 8-12” high, blue-silver foliage
• Deer grass (muhlenbergia rigens) – 3’ tall plus plumes
• Giant wild rye or Canyon Prince wild rye (Leymus condensatus) – large clumping grass, 4-5’ across and 6-8’ tall in bloom. Canyon Prince has silver-gray foliage.

We’ve grown all but the giant wild rye.

Others to consider include blue oat grass, lavender and San Diego sedge.

SHRUBS

Instead of:

Broom (all types, which have numerous botanical names), acacia or western coastal wattle (acacia Cyclops) and myosporum (Myosporum laetum)

Why? While brooms have a pretty flower, they’ve invaded over one million acres in California. All three grow very fast and produce numerous seeds, displacing native vegetation, and increase fire risk.

Consider:

Clayton recommends the following:

• Cleveland sage (salvia clevelandii) – green-gray leaves, needs good drainage, strong sage scent
• Toyon (heteromeles arbutifolia) – can grow 15’, birds love the bright red berries in November/December

  

• Lemonadeberry (Rhus integrifolia) – 8’ tall, sensitive to significant frost;
• Coffeeberry (Rhamnus californica, such as Eve Case ) – dark green leaves, does well in part-shade
• Catalina Cherry (Prunus lyonii) – can grow to 25’, does better with water, beautiful white flowers
• Hollyleaf cherry (Prunus ilicifolia) – grows to 14’, birds love the fruit which is edible
• White Sage (Salvia apiana) – leaves become smooth white, attracts bees and hummingbirds.

We’ve planted all of these and all have done very well in our inland climate.

Others to consider include bush marigold (Tagetes lemmonii), bush poppy (Dendromecon rigida), pineapple guava (Acca sellowiana)

Where to buy these substitutes

Nurseries specializing in native plants, such as Mockingbird Nurseries in Riverside, Rancho Santa Ana Botanic Garden in Claremont and Las Pilitas in Escondido should carry all the natives. Many other nurseries will carry some of these such as blue fescue, Cleveland sage, coffeeberry, toyon, or can often order them.

For more information:

Las Pilitas website www.laspilitas.com – has great descriptions on native plants.

California Invasive Plant Council – www.cal-ipc.org