Tall bearded irises are among the most dramatically beautiful flowers in our gardens, but they are not carefree. Ignore them for three or four years and the quantity of blooms will peter out, the iris patch will become crowded with their roots, and the sword-like leaves will lose their bright green youthful look.
The cure for this malaise is to renovate the iris bed every three years. You will be rewarded for your efforts with gorgeous flowers that will look fresh and forever young.
Before describing how to renovate a bed, let’s take a look at irises in general. The genus is named for the ancient Greek goddess Iris, who was the personification of the rainbow. It’s an apt name, given the full spectrum of colors in our modern irises. Because of their beauty, hybridizers have created thousands of named varieties of bearded iris over several centuries; in addition, there are several hundred wild species of irises known around the world, so the genus is vast.
The most popular and familiar kind of iris in the United States is the bearded iris, also known as the German iris. Each blossom has three upright petals called standards, and three downward-curving sepals called falls. Each fall has a “beard” that emerges from its base and lays down partway along the fall’s length, looking much like a fuzzy caterpillar.
There’s an old gardener’s saying that irises smell like their color. And there’s some truth to that. These flowers are subtly fragrant, and it’s easy enough to convince yourself that a purple iris smells like grape jelly, or a white one smells like vanilla. But before you go poking your nose down into the reproductive apparatus of an iris flower, make sure a bee isn’t already working there.
If you’re starting a new iris bed, just follow these instructions for renovating a bed, except you’ll be starting with dormant roots. Right now — the end of September and the beginning of October — is the perfect time to refresh an iris bed. Here’s what to do:
Using a spading fork, dig up the bed, shoving the tines underneath the roots and prying them up so they’re loose on the surface. Shake or thump each plant to remove most of the soil, then place them aside on a tarp or in a wheelbarrow.
Irises like summer moisture, but they don’t like to stand in water or their rhizomes (roots) may rot, so good drainage is imperative. Make a raised bed on poorly drained soil, or dig deeply to loosen hard-packed soil. Add lots of well-made, finished compost: a 6-inch-deep layer over the bed is not too much. You really can’t use too much compost. It nourishes your irises and gives fluffy texture and tilth to the soil. It also holds water like a sponge so the bed will stay moist longer during our summer drought. Dig the compost into the top foot of soil.
Now examine each plant. You’ll notice the leaves emerge from the growing end of a longer, segmented root. The part of the root where the leaves emerge will also have the freshest-looking whitish roots. The segments farthest from the growing end are remnants of previous years’ growth. Break them off the growing segment with your hands or cut them off with a sharp knife and discard them.
Sonoma’s Bartholomew Memorial Park
(Closed from January 1 to April 1)
Hiking distance: 2.4-mile loop
Hiking time: 1.5 hours
Elevation gain: 450 feet
Difficulty: easy to moderate
Exposure: a mix of open meadows and shaded forest
Maps: U.S.G.S. Sonoma, Bartholomew Foundation Trail Map
Bartholomew Memorial Park is a little known gem tucked into the hills less than two miles northeast of Sonoma. The 375-acre park leases part of its diverse land to Bartholomew Winery. This hike is not a meandering stroll through a winery, it only begins and ends there. The trail is a backcountry hike winding through oak-covered mountain slopes and redwood groves. The hike follows portions of Arroyo Seco and the South Fork of Arroyo Seco to a pond, lake, cave, and two impressive overlooks.
To the trailhead
1695 Castle Road, Sonoma
From East Napa Street by the Sonoma Plaza in downtown Sonoma, drive one mile east on East Napa Street to Seventh Street East. Turn left and continue 0.3 miles to Castle Road. Turn right and drive 0.4 miles to the Bartholomew Park Winery entrance. Enter the winery grounds and go a quarter mile to a road fork. The right fork leads to the tasting room. Veer left 0.1 mile to the trailhead parking lot.
A second trailhead is located off Old Winery Road. From East Napa Street, just east of Eighth Street East, turn north on Old Winery Road. Drive 0.75 miles to the posted trailhead parking area on the left.
From the north end of the parking lot, -follow the posted trail 40 yards to Duck Pond. Curve right along the east side of the pond to a trail gate. Pass through the gate and cross a stream in an oak, manzanita, and madrone forest. Climb the hill on the Grape Stomp Trail and traverse the slope, parallel to the stream. Head up the shaded draw and recross the stream. Climb steps and zigzag up the hill to Grape Stomp Bench and an overlook of Sonoma and San Pablo Bay. Weave along the contours of the hills with small dips and rises. Descend to a fork of Arroyo Seco Creek by a private road.
Rock-hop over the creek and cross the road. Climb eight steps and head up the forested hillside. Follow the north side of Arroyo Seco Creek, passing above Benicia’s Lake. Descend steps and hop over the creek upstream of the lake. Enter a redwood grove with Douglas fir and continue climbing. A side path on the right leads to the east shore of the lake. The main trail continues to a posted junction at one mile. Angel’s Flight Trail descends to the right for a slightly shorter and easier loop.
Bear left on the You-Walk Miwok Trail, climbing to the 640-foot summit that is just past a bench. On clear days, the vistas extend as far as the Golden Gate Bridge. Descend from the upper slope, with the aid of dirt and log steps, to the Shortcut Trail on the right. Stay straight 20 yards to a side path on the right to Szeptaj Point bench, with beautiful views of Sonoma from under a canopy of oaks. Continue downhill on the main trail to a posted junction. Detour to the left 80 yards. Follow the South Fork of Arroyo Seco upstream, passing small waterfalls. Continue over mossy boulders to Solano’s Hideaway, a massive rock formation with caves. Solano was an Indian chief of the Suisun Tribe and a friend of General Vallejo.
Return to the junction and continue west, passing a junction with the lower south end of Angel’s Flight Trail. Pass through a trail gate and skirt the backside of the Buena Vista Winery. Pass through a second gate to a narrow paved road by a gazebo on the left. Cross a rock bridge over Arroyo Seco Stream and follow the path on the right side of the road. Cross Castle Road and complete the loop at the trailhead parking lot.
Source: “Day Hikes Around Sonoma County” by Robert Stone (Day Hike Books, 2016)