Calling all gardeners! There are a number of escaped invasive plants on the loose in the Sierra Foothills and they are moving up the mountain. We must be vigilant and eradicate them. They are threatening the delicate balance of life that makes the Sierra so beautiful. Don’t get caught aiding and abetting these big bad bullies.
You will recognize some of these plants by their aliases. If you have any of these on your property, pull them up at once. Even though you think they are pretty, they are destructive and will multiply by nefarious underground systems of rhizomes and by pollen floating on the wind.
There is hope for the guilty gardener, though, so don’t despair. There are alternative plants that aren’t invasive and have the same aesthetic characteristics as the bad ones. Your garden will look just as pretty using these non-invasive substitutes.
Here is the line-up of the guilty invasive plants still at large:
Villain: Arundo donax – aka: Giant reed. These plants resemble bamboo and can grow up to four inches a day and can reach a height of 30 feet. People use them for screens, fences, and erosion control.
Instead, plant clumping bamboo. This works well as fencing and isn’t invasive. It has beautiful stems and delicate leaves and many varieties will withstand the cold of the Sierra Nevada. Be sure to note the cold hardiness of the variety before you buy it.
Villain: Cytisus scoparius – aka: Scotch broom. All the brooms are invasive: Scotch, French, bridal veil, and Spanish brooms. Yes, they are very pretty, but they are so invasive that they are popping up everywhere. They come up year after year – even after valiant efforts at eradication.
Instead, plant forsythia. It has beautiful yellow flowers that bloom in winter and early spring. These plants can be pruned and trained to fit into any garden setting. They need full sun and moderate water to thrive.
Or, instead of brooms, plant shrubby cinquefoil (Potentilla fruticosa). This plant grows well in the Sierra Nevada and is easy to cultivate. It has many different colors, depending on the variety: pink, white, yellow or orange.
Villain: Vinca major – aka: periwinkle. This plant has blue-purple flowers and, though lovely as a ground cover, spreads unchecked by its sprawling stems that sprout roots at the node. Even a small fragment is sufficient to engender a new population. It is also commonly spread by yard waste being dumped. Don’t plant this villain!
Instead of this, plant hardy geraniums (Geranium ‘Rozanne’). Plant them in full to partial sun, depending on the climate. It has moderate water needs and stays evergreen in milder climates. The flowers are blue to violet, similar to those of the periwinkle.
Another beautiful substitute for the periwinkle is the Serbian bellflower (Campanula poscharskyana). It looks like periwinkle in color and shape but is non-invasive. It is a perennial with vigorous growth. It grows up to eight inches high and spreads, making it ideal as a groundcover. Flowers appear in spring to early summer.
Villain: Pennisetum setaceum – aka: green fountain grass. This spreads copiously throughout an area and its seeds remain viable in the soil for at least seven years. One of the most villainous of the villains!
The perfect alternative to this – with the exact same effect – is purple fountain grass (Pennisetum setaceum). The only difference is the purple of the spire-like leaves and it is actually prettier than the green variety.
Before planting in your Sierra garden, check out these two Internet sites: www.plantright.org, and www.cal-ipc.org. They are easy to navigate and are chock-full of information on the proper plants for our area.
Don’t throw your invasive plants out with yard waste – they can and will propagate! Burn or dry them in the sun until dead.
As responsible gardeners, let’s keep the Sierra Nevada Mountains healthy and beautiful. We don’t want to be accomplices to the spread of non-native, invasive plants.
Sources: plantright.org and cal-ipc.org
Francie McGowan is a BAT (Bay Area Transplant) who now lives full-time in the Sierra Nevada. She’s learning that higher-elevation gardening is very different from Bay Area gardening.