BY Jack Heeger
Chateau Montelena (Calistoga, Napa Valley) has gained a reputation
over the past three decades as a producer of high quality wines,
particularly Cabernet Sauvignon. Dave Vella, vineyard manager, tends
nearly 200 acres of vineyards and credits the high quality to vineyard
The estate vineyards are located in a special place, where
the soils and climate and slope have come together to create the
perfect spot to grow Cabernet Sauvignon, Vella explains. Our
location makes growing great fruit easy.
Other factors also contribute to Chateau Montelenas success,
especially some very careful sustainable vineyard practices that
have played a major role in taking advantage of everything the winerys
seven vineyard locations offer.
About two-thirds of Chateau Montelenas approximately 32,000
annual case production is Cabernet Sauvignon; most of the remainder
is Chardonnay, with a small amount of Zinfandel and Mendocino County
The Estate Vineyard is the Montelenas largest (about 115 acres).
Eighty-three acres are planted to Cabernet Sauvignon, nearly 20
to Zinfandel and Primitivo, and the remainder to Merlot and Cabernet
Franc, which are blended into the winerys Napa Valley Cabernet
Other vineyards surrounding the estate include Vellas personal
12.5 acres planted to Cabernet Sauvignon; Barberis, with 28 acres
of Cabernet Sauvignon and Merlot; Montelena Blossom Creek (15 acres)
and Montelena Garnet Creek (six acres), both planted to Cabernet
Sauvignon, and Wolleson, an eight-acre vineyard just south of Calistoga
planted to Cabernet Sauvignon.
In addition, Chateau Montelena leases a 55-acre vineyard in the
Oak Knoll District at the base of Mt. Veeder near Dry Creek Road,
where mostly Chardonnay grapes are grown.
Vella supervises all the owned and leased vineyards, including Oak
Knoll, but the hands-on manager at Oak Knoll is Bill Hanna, who
planted the vineyard for owner Frank Takahashi.
Hanna owns and manages a neighboring vineyard from which Chateau
Montelena sources Chardonnay. Hannas vineyard produced about
half of the Chardonnay bottling that was rated tops in the famed
1976 Paris tasting.
Vella is assisted at the Napa Valley properties by four full-time
employees, all of whom have been with Montelena for 17 years or
Chateau Montelena produces about 1,500 cases of Riesling from purchased
grapes grown in Potter Valley.
Yield at Montelenas vineyards is generally between one and
two tons per acre for Cabernet Sauvignon (planted in the 1970s),
Cabernet Franc, and Primitivo/Zinfandel. Merlot vines are more closely
spaced and can yield three to four tons per acre.
The estate vineyard has Bale, Cole, and Kid series soils that were
formed from alluvial and sedimentary parent materials in the lower
elevation vineyards and Cortina and Pleasanton series soils that
were formed in volcanic parent materials, such as rhyolite in hillside
Montelenas vineyards elsewhere in the Calistoga district are
all located adjacent to tributaries of the Napa River and most have
alluvial soil, with cobbly, gravelly subsoil, allowing deep root
penetration and good drainage with medium (highly variable) water-holding
capacity, resulting in moderate vigor.
Six acres of estate Cabernet Sauvignon are planted on Bale and Cole
series that are sedimentary soils with a high percentage of clay,
producing more vigor, and hillside blocks at upper elevations are
planted on rocky, well-drained volcanic soil.
Chardonnay vineyards in Oak Knoll are planted in Haire-loam soil,
which contains considerable sedimentary material, such as decomposed
shale and blue/gray clay, with moderate drainage.
From his start in 1985, Vella had been maintaining the vineyard
soils with annual applications of chicken manure and compost. Feeling
that he needed a better balance, Vella set about to enhance the
In college, in soils class, you learn that if youre
looking at this type of soil then you add this nutrient, Vella
says. But thats not how it really works.
One day Vella attended a meeting at which Bob Shaffer, an agronomist
with Soil Culture Consulting, spoke. As Shaffer addressed the group,
Vella thought, Hes talking about exactly what Im
experiencing. Chateau Montelena hired Shaffer as a consultant
in 1994, and he has been working with the winery ever since, making
soil health improvements.
Weve done it in small increments, Vella explains,
in deference to his concern for making mistakes by changing things
For example, with low fertility soil, he asks himself, What
did weed growth patterns look like before the vineyard was planted
and vine growth began?
Weeds are plants growing on soils with mineral balance and
cultural practices that limit more favorable species from growing,
explains Shaffer. Each plant has an ecological niche where
they are most successful. Soils with excess nitrogen, poor structure,
and low soil organic matter content are conducive to coarse weeds
like star thistle, little mallow, and marestail, for example.
The balance of soil minerals, especially nitrate nitrogen,
calcium, and magnesium, and cultural practices largely determines
the species and density of resident vegetation in a vineyard. Systematic
selection and management of cover crops, in conjunction with developing
good soil mineral balance and developing soil organic matter, is
the most effective and economical form of weed management for a
Vella did soil analyses and took tissue samples, but he says, My
biggest fear was changing something that was working, so we went
into soil enhancement very cautiously.
But Shaffer, who took the first soil sample at Montelena in 1994
and began work in earnest in 1999, says winery staff
has been very supportive in making changes. I respect Chateau
Montelena personnel for what theyre willing to learn and for
their desire to build a program for soil health over time, that
acknowledges the existing cultural practices.
A soil analysis is done every year on samples taken from three to
ten acres maximum in each vineyard. Shaffers first soil analysis
revealed that winery soils are part of the Pleasanton and Bale soil
series, and I was already familiar with those soils series,
Shaffer recalls. I knew the estate soils would greatly benefit
from improved mineral balance and elevating the soil organic matter
level even though these two series of soils are very different in
The balancing of minerals and introduction of more organic
matter into the soil are synergistic with each other and create
elevated levels of soil health that provide many substantial benefits
to vines such as improved fruit quality and prevention of diseases.
Addition of minerals, nutrients, and organic matter to Chateau Montelenas
vineyards began in 1999 with soil application of mined minerals,
such as rock phosphate, potassium sulfate, calcium carbonate, and
calcium sulfate, as high-quality sources of slow-release minerals.
Quantities are determined by soil analyses, which should be conducted
annually because the quantities of minerals used will differ from
year to year. For example, Shaffer notes that boron and sulfur must
be applied more frequently because they are easily leached.
Minerals are applied whenever its convenient and fits
into the work schedule before the rainy season, adds Shaffer.
It takes rain to make them work and become available in the
A cover crop was seeded in 2001 at Chateau Montelena, with crimson
clover and barley in lower elevation vineyards and rose clover and
zorro fescue on hillsides. It was beautiful, notes Shaffer,
but it also added to the soil.
Each year since 2001, we have rotated and diversified the
cover crop species to include both annuals and perennials including
clovers, grains, California native grasses, European grasses, herbs,
and flowers. We select and cultivate cover crops for soil health
features such as erosion prevention, increasing soil organic matter,
water holding capacity and infiltration, and elevating soil food
Additionally, we have employed cover crops to act as a habitat
and food resource for beneficial life in the vineyards such as predator
or parasitic arthropods, insectivorous birds, and beneficial vertebrates
like weasels and foxes. Culturing a diversity of plants with good
strategic placement within the vineyards and which can provide pollen,
nectar, and habitat over the grape cropping cycle is the goal of
beneficial insectary plantings.
Plants like alyssum, buckwheat, carrot, crimson clover, common
vetch, and yarrow, in addition to many resident grasses, wildflowers,
and forbs are great choices to cultivate in a vineyard for supporting
beneficial life and decreasing pests. There was a clearly noticeable
increase in the estate vineyards populations of green lacewings,
brown lacewings, six spotted thrips, and other generalist predators
of vine pests where blooming plants were maintained.
By using select species of some plants, such as crimson clover,
we found that cover crops could encourage tremendous levels of beneficial
green and brown lacewings, Shaffer adds.
The goal for planting cover crop is two-fold: to benefit everything
above ground prevent soil erosion, encourage beneficial life
forms, prevent dust, and improve vineyard appearance and
to enhance everything below ground, including better water infiltration.
This allows minerals to be transformed into plant-available forms.
Shaffer adds that both beneficial life (predators) and pests (prey)
are dependent on prefixed carbon as their sole dietary energy source.
The trick is to develop a cover crop system in vineyards that
tolerates low populations of prey that acts to sustain large populations
of healthy beneficial predator organisms throughout the cropping
cycle. This way, the cover crop is not only a critical component
of soil erosion prevention, soil health, vine health, and fruit
quality development, but is also an active component of above-ground
pest damage prevention.
In addition to the carbon in living plant tissues, pollen and nectar
are alternative sources of food for beneficial predators, and some
cover crops offer more benefit than others. Examples are plants
with long bloom cycles, such as alyssum, that support predators
over the entire summer and winter, and plants with extra floral
nectar sites, such as common vetch and bell beans, which offer large,
easily accessible volumes of nectar.
Shaffer recommends maintaining various species of grasses and other
plants that bloom at different times to provide continuous, overlapping,
and diverse food for beneficial life in vineyards.
Below-ground cover crops are the most practical means to increase
the soils available carbon content, which is the sole energy
source for the living microbial biomass. The soils living
microbial biomass provides both biological and chemiophysical advantages
to vines growing in soils with plant-parasitic nematodes.
Cover crops deposit carbon into soils by their roots
exudation and by organic matter when the roots die. North coast
soils are generally seriously carbon-limited and without adequate
annual return of organic matter, these soils can become disease-conductive.
Soil carbon is the sole energy source for the beneficial bacteria,
fungi, and nematodes that act to control plant-parasitic nematodes.
With synthesis of organic matter by plants and the carbon
it contains, cover crops provide the most economical, practical,
and effective energy source for the living microbial biomass that
directly benefit grapevines with the seven essential functions performed
by soil food web activity. Other non-living fractions of the soil,
such as minerals, humic materials, and non-humic materials are also
important sources of nutrition for the live biomass and soil food
web functions in soil.
Selection of cover crop species, used in conjunction with
mineral balance and compost, can also act to decrease the negative
impacts of plant-parasitic nematodes such as Dagger and Rootknot
nematode in vineyards. Cover crop species can be selected to be
either non-host or directly toxic to plant-parasitic nematodes.
Non-host species are those that do not suit the plant-parasitic
nematodes diet requirements, and therefore weakens them.
Cruciferous plants, such as white mustard, contain glucosinolates
that, upon decomposition in the soil, release isothiocyanate that
can lower the population of plant-parasitic nematodes, weed seeds,
and fungal pathogens.
Our goal in composting is foremost to recycle winery by-products
and, upon application, to increase the vineyards soil heath,
says Shaffer. The feedstock, processing, and curing are intended
to create a compost that has disease-suppressive character. Windrow
and static pile techniques are employed, with plenty of woody materials
which feeds fungi in the compost and has a fairly coarse texture,
allowing for good air circulation and high populations of beneficial
microbes in general.
We know that, by biological analysis, the estate soils would
benefit greatly by higher populations of diverse species of fungi.
The compost is intended to inoculate the soil with fungi and to
feed all the soils macro- and micro-organisms, which then
feeds the vine the best possible forms of nutrition.
A typical compost pile at Chateau Montelena contains about 65% pomace,
about 10% chicken manure, 20% woody materials (such as wood chips
and wood shavings from barrels), and about 5% compost from the previous
pile to act as a starter.
Fresh water plants from Jade Lake on the estate are harvested
from time to time and added thats a good inoculant,
Shaffer says. These water plants simply are another source
of diversity, and a recycled material.
Soil amendments including rock powders such as calcium phosphate,
basalt or calcium carbonate are also excellent compost feedstocks.
There are four groups of functional living organisms (bacteria,
fungi, nematodes, and protozoa) referred to as the living
microbial biomass in soil that provide seven critical benefits
that are unavailable from any other means, says Shaffer. Well-made
and fully-cured compost increases the health of the living microbial
biomass and benefits vines in seven ways that are critical for vine
For best grapevine growth, we want minerals in soil to be
balanced, which refers to both the ratio of the major cations and
anions to each other in soils, and also the overall poundage of
all essential minerals in soil. Managing mineral balance requires
the use of wet chemistry soil analysis to determine the relative
balance that currently exists, and improves the predictable outcome
of soil inputs.
Mineral balance and the living microbial biomass in soils
controls the pH, rate of mineralization, organic matter decomposition,
soil structure, vine health, and significantly affects the quality
of fruit production. Soil minerals vary greatly in content in soils
due to parent materials, farming practices, leaching or fixation.
Soil mineral balance is generally better near the surface of the
soil and is less desirable deeper in soil.
For example, the alluvium and sedimentary soil at the estate
are high in potassium due to decomposition of a potassium-rich volcanic
rock called Rhyolite that formed from post shield stage lava from
Mt. St. Helena. Grapevines and fruit require good potassium availability
for their best quality and Chateau Montelena soils provide luxury
amounts of potassium.
However, potassium is antagonistic to calcium, boron, and
manganese that are also required for high-quality grapes. By measuring
the soils mineral balance, we can predict the right amounts
of calcium, boron, and manganese required to balance
the high potassium. Here again, soil organic matter plays a critical
role in buffering the negative effects of an excessive mineral and
by chelating minerals into forms that are most usable by grapevines.
Minerals in the soil have antagonistic effects on each other.
Minerals in soils do not exist in a vacuum and are subject to chemical
and biological forces that either increase or decrease their availability
to plant roots. By following scientific guidelines to balance
the essential soil minerals, vines produce a higher degree of fruit
quality and elevated disease resistance or tolerance.
Cover crops, compost, and mineral balance act synergistically to
elevate soil health, which support healthy earthworm populations.
Earthworms are indicator species of soil health.
Soil treatments have increased earthworm activity in the soil at
Chateau Montelena. We try to delay any required spring tillage
until the earthworms have moved deep into the soil as they follow
the moisture downward, Shaffer explains.
Benefits of earthworms, the largest animal in the soil system, are
profound, notes Shaffer. They accelerate decomposition of
organic matter, and they make holes deep in the soil, creating a
path for water and air. Earthworms improve soil structure,
consume plant-parasitic nematodes, and they change minerals into
forms more effective for root uptake.
The more you learn about earthworms, the more you protect
them, Shaffer declares.
Earthworms are an important component in our effort to limit mechanical
tillage because the earthworms actually are tillers. They
work 24 hours a day, seven days a week with only the cost of some
cover crop residues and good mineral balance, he concludes.
Vella reports that 16 different blocks of Cabernet Sauvignon are
planted at Chateau Montelena, and because of low vine vigor, the
grapes produce an earthy, deep, dark-colored wine. Six acres planted
on heavy clay, sedimentary soil have more vigor and the vines yield
about 20% more fruit than the rest of the block. Vella notes that
the wines produced from these vines are more typical of Napa Valley
wine. Hillside blocks on the volcanic, rocky and well-drained soils
of the higher elevations of the Chateau Montelena property produce
a low-yield but intensely concentrated fruit.
The majority of the Montelena vines are more than 30 years old,
and although the trend when they were planted was to use AXR-1 rootstock,
the winery chose St. George, and did not experience a phylloxera
problem. In 2002 and 2003, 10 acres of Chardonnay in Oak Knoll were
replanted with 101-14 rootstock and Clone 4 and 17 scion-wood. At
the Home Ranch in 2001 and 2003, eight acres were replanted with
110-R rootstock and clone 337 Cabernet Sauvignon.
The winery has nearly 63,000 vines, ranging from 454 to 906 vines
per acre. Eighty percent of them are from the original planting
Vineyards were originally planted 12x8, typical for 30 years ago,
but replanting is 8x6, mostly on vertical trellising. Montelena
has vertical, lyre, and two-wire trellising, depending on location,
soil type, and varietal.
There is one six-acre block in the Montelena Estate Vineyard where
Vella could not control the canopy properly, resulting in poor quality
grapes, that has been converted to a lyre system and now the
grapes make the cut every year.
Extensive leaf removal is done on head-trained vines to open up
the center, but not much de-leafing on the canes. Leaves are removed
after bloom, again when the berries are pea-size, and one more time
around veraison. If its cool or we have a late rain,
well do another pass on the Zinfandel and Primitivo,
Leaves are pulled from all sides. Weve had more burn
on the morning side than on the afternoon side, he notes.
But every vine is different.
Vella does cane pruning because it removes more wood and reduces
potential Eutypa and Pierces disease. Our 30-year-old
vines are more susceptible to Eutypa, he says. We prune
as late as possible we start the latter half of December.
We wait as late as we can.
Theres no specific formula for pruning. The crew looks at
each vine individually and prunes to an average of 1 1/2 to 1 3/4
canes per vine. Id like to average two, Vella
says, but it all depends on the previous years growth.
Chateau Montelena practices sustainable farming. Insect infestations
have never been a problem according to Vella, but he has about 750,000
ladybugs released in late spring, just to make myself feel
like Im doing something. In addition to eliminating
the use of soluble fertilizers and relying on the pomace, wood,
manure recipe compost, Vella refrains from using herbicides, relying
on an old-fashioned French plow where possible to keep the vineyard
free of weeds.
His crew makes one pass with the plow in the spring, preferably
before bloom, but always after bud break. Suckering is done during
leaf removal, and, during this time, the crew also looks for weeds.
The first suckering is done on the trunk and head before bloom.
A mower, hoe plow, and disc are used to handle the cover crop. On
the valley floor, the cover crop is mowed after bud break, when
weather allows. We may wait longer than others, Vella
acknowledges, but we will not allow tractors on the soil when
the ground is wet.
The crew discs between four and eight inches deep, depending on
how hard the ground is, and on the hillsides its necessary
to mow as often as four times per year. We have to irrigate
the hillsides, so we get more weeds there, Vella notes.
No irrigation is given to most Cabernet Sauvignon vines on the valley
floor, but Vella has experimented with irrigation on hillsides to
get the right formula. Its not on a schedule,
he says. Just when it looks ready. He may water up to
two weeks before harvest. Typical irrigation for rocky hillside
blocks is 6 to 7 gallons/week.
The first thiolux application is after bud break, the second is
just before bloom. A typical season would include two applications
of thiolux and two or three sulfur dustings.
For frost protection, Chateau Montelena has 13 wind machines and
about 25 acres under sprinklers. Hillside blocks are unprotected.
Vella plans on a 60-day window for frost after bud break, and in
2004, used wind machines and sprinklers only three times. But in
2005, they came into play 11 times.
An intangible asset
In addition to the viticulture practices employed by Chateau Montelena,
another element plays a major role in making the world-class wines
for which the winery is known.
A long and special relationship between Vella and winemaker Barrett
brings an intangible asset to the winery. Vella and Barrett were
classmates at Fresno State and developed a close friendship. Vella
graduated with dual degrees in enology and viticulture and afterwards
worked as the only full-time employee for a small winery in Napa
Valley, handling every aspect of the winegrowing and winemaking
In 1985, when Chateau Montelenas vineyard manager, John Rolleri,
was about to retire, Barrett called Vella and offered him the job,
saying he was looking for an experienced vineyard manager who also
had a winemakers perspective. Vella wondered if good friends
would be able to work together without ruining the friendship, but
he decided to give it a try, and the relationship has worked perfectly
and the friendship survives.
The two trust each other implicitly and work very closely together
when harvest comes. Vella and Barrett make a joint decision on when
to pick, and they have established what they call a veto power
voting system. If they do not agree, they hold off picking, because
both believe it is better to wait than pick too soon.
All these factors excellent vineyard locations; careful selection
of rootstocks and clones to match the soils and climatic conditions
of individual blocks; soil management with annual soil analyses;
cover crops; and the close working relationship between vineyard
manager and winemaker work together to produce the high-quality
grapes that allow Chateau Montelena to sell its Napa Valley Cabernet
Sauvignon for $40, estate Cabernet Sauvignon for $125, and Napa
Valley Chardonnay for $35/bottle.