Filoli’s planned water conservation measures and recommendations.
Find out what's blooming at Filoli from January to December.
Learn about Filoli plants and gardening practices—ask the experts.
Nov. 28-Dec. 6. Dining, shopping, and holiday music.
Plant Highlights This Week
Flowers are one of the most pronounced markers of the progression of time in a garden. Each month we scout the Garden for amazing blooms and feature our favorites here. Check back often to see what we have in store for your next visit to Filoli.
Week of October 20 - 26, 2014
Last report for the season- see you next February.
As of last Friday, all of our bulbs have arrived! Until everything is here, it is a bit stressful wondering if the ships, trains, trucks, mail carriers, etc. that carry our bulbs will get everything to us safe and sound. Planting will begin this week in both the Sunken Garden and with some of the Walled Garden beds.
Some of the varieties to look forward to next spring include, ‘Menton’ in the Sunken Garden, the peony-flowered ‘Peach Blossom’ in the Garden House Beds, and the peony-flowered ‘Romantic Mixture’ on the Dining Room Terrace Beds.
Plant of the Week:
One of the more obscure plants in the garden most of year because of its location and, often, lack of showiness, is the mountain witch hazel (Fothergilla major) behind the pool pavilion. Most of the year, this 8-10’ shrub is hardly noticeable among the rhododendrons in this bed beyond the lawn behind the pavilion. Though its green, corrugated leaves are interesting up close, they hardly are eye-catching.
There are two times during the year, however, when this plant shines: early spring and in fall. In spring, the branches are terminated by bottle brush-like inflorescences. These flowers emerge before the leaves have formed. Creamy white, they are like points of light all over the plant. They are also intoxicatingly fragrant with a honey-like aroma.
Right now is the other time of year when the shrub catches people’s attention. Most members of the witch hazel family (Hamamelidaceae) have fantastic fall color, including other witch hazels (Hamamelis spp.), winter hazel (Corylopsis spp.), sweet gum (Liquidambar styraciflua), and the Persian witch-hazel (Parrotia persica). While many of these trees and shrubs turn shades of red in fall, mountain witch hazel turns brilliant yellow-orange. Often in contrast to the greens surrounding it, this plant, again, is like a beacon on a dark night. One’s eye is traveling along and, BAM!, it spots the brilliant, golden leaves.
Like most witch hazels, mountain witch hazel prefers an acid soil. Although our shrub is under oak trees, it would flower somewhat better in a sunnier spot. Otherwise, this shrubs needs a bit of shaping when young and benefits from deadheading in later spring. As with many woodland plants, they do require regular irrigation.
Beyond the fall color/interest of the mountain witch hazel, other showy plants include the Virginia creeper (Parthenocissus), the peaches in the fruit orchard, the pomegranates behind the main house, various trees around the Woodland Garden.
The Sasanqua camellias have begun blooming in and around the garden. There is a very nice variety of blooms behind the Garden Shop in what we call the Camellia Island. Many around the walled garden are in full bloom as well. Be sure to stop and smell the sweet, earthly fragrance of these flowers.
Several of the summer beds are still looking very nice, particularly the begonia and SunPatiens displays. The Dutch planting of Begonia ‘BIG Red with Green Leaf’ is over three feet tall at this point. Other BIG begonias are located in the West Reception Beds and the Dining Room Terrace. Though their foliage is starting to turn grey from powdery mildew, the dahlias are still blooming away.
The Kitchen Garden is still impressive, but is transitioning from summer bounty to fall interest. The Brussels sprouts are rising up and producing sprouts along their stalks. The gourd and pumpkin plants are fading, but the squashes are still showy. The ‘Cayenne’ and ‘Thai Hot’ peppers are covered with shiny red fruits.
The cutting garden still has a lot of flower color, but also is showing fall color in some of the perennials including the herbaceous and tree peonies.
Prepping for fall planting and pollarding plane trees are the biggest projects this week.
Notes and Common Questions
A plant the horticulturists, and volunteers as well, are being asked about recently, concerns the stunning southern magnolia (Magnolia grandifloria) guests encounter as they approach the house and garden from the Visitor’s Center. This magnolia, one in the collection of magnolias added to the front of the house by Mrs. Roth, often introduces visitors to the high horticultural standards for which our gardens are known. (I can still remember seeing the tree when I visited Filoli for the first time on a rainy, spring day in 1994.) The question is in regard to the thinning canopy on the southeast side of the tree. The branches are not as full and the color is a bit off from the rest of the tree.
The short answer is that we are still unsure what is causing the lack of vigor. We had wood samples tested from the top of the canopy, and nothing came back conclusive. Visually, the condition looks more like a Verticillium wilt, but none of the samples showed it was this fungal pathogen. We also had the roots tested, which showed Phyophthora, a root rot fungus, but this is common in our soils, and would show symptoms throughout the canopy.
Recommendations we’re received, and the actions we are taking include giving the tree supplemental water through the summer and composting under the canopy. We’ve increased the water the past few weeks and plan to mulch with 4” of compost in the coming months. We’re hopeful that with some TLC the tree will grow out of the condition and begin to fill back in over time.
The Filoli drought page is on our website (http://www.filoli.org/drought/). As many have noted upon visiting this summer, many of our lower-profile lawns are somewhat to completely brown. We’ve also reduced our water use in our orchards and any other woody plantings by approximately 40%. We felt that these two major reductions in irrigation use would be the best ways we could do our part in conserving water along with everyone else in California. At this mid-year point, Dave Herrington, head of our maintenance team, reports that we have reduced our total water use by over 55% over last year! Considering that last year was the driest calendar year on record, and that we had no conservation plan in place, with our use up approximately 25%, the outstanding savings this year might be somewhat inflated. That said, looking back to 2012, we’re still probably saving 45-50% over a typical rain year.
The Colors of Hydrangeas
In the wild, Hydrangea macrophylla, which is native to Japan, has pink flowers. Over the last century, different cultivars (cultivated varieties) have been bred to have darker pink, blue, or white flowers. To understand color change in hydrangea flowers, we have to delve into some basic chemistry. Hydrangeas prefer a slightly acid soil (pH 6.0-6.2). At this pH, hydrangeas will maintain their original color. As the soil approaches neutrality, and then becomes alkaline (above pH 7.0), and aluminum becomes less available to the plant, and thus, the pinks will become darker pink and the lighter blue shade will turn pink. In acid soils (lower pH), the pink flowers will become blue and the pale blue will become dark blue or purple. The exact shade of blue depends on the original color, how acidic the soil is and how much aluminum is available to the plant. White flowers will not change color with changes in soil chemistry.
At Filoli, to acidify our soil and enhance the color of our blue hydrangeas, we add one-quarter to one-half pound of granular aluminum sulfate around the base of each large plant in November. If your soil is in the neutral range, it is fairly easy with the addition of aluminum sulfate to enhance the blue color in hydrangeas. It is much more difficult to achieve an alkaline soil, but this can be done by adding dolomitic lime several times a year around your plants. If your soil naturally runs acid or alkaline, it can be extremely difficult to sway your soil to the opposite end of the spectrum.
For more information on Filoli’s hydrangea care, please see the Garden Resource Center page of the Filoli website (http://www.filoli.org/garden-reference/). Here you will find a reference sheet on hydrangea care, many other Filoli plants, as well as other garden maintenance situations.
Bloomin' Bucks Program
Whenever visitors, volunteers or anyone else asks about where Filoli purchases our bulbs, after telling them that the bulk of our bulbs are purchased wholesale from the Netherlands, I tell them the best retail vendor in the US that I know is Brent and Becky’s Bulbs. Brent Heath’s family has long been in the bulb business and because of their lasting relationships with the Dutch growers, Brent and Becky are able to sell top quality bulbs. If Filoli could afford to buy all of their bulbs from this company, we would.
As part of the company’s commitment to public gardens, schools and other non-profits, Brent and Becky established the Bloomin’ Bucks program. With each purchase from Brent and Becky’s through the program, the designated non-profit receives 25% of the funds. Filoli is a participant in this program. So, if you’re planning to order bulbs this year, and like Brent and Becky’s products, please go to the Bloomin’ Bucks page (www.bloominbucks.com) to start your purchase by choosing Filoli as your non-profit of choice. From there, you will be sent to the regular Brent and Becky’s Bulbs website to start your shopping.
Written by Jim Salyards, Filoli's Manager of Horticultural Collections and Education, and Internship Program Coordinator