Tannins formed in mountain grapes are softer, producing more
drinkable wines. Vines grown in thin (2 to 6 feet depth) mountain
soils produce soft tannins and small berries for more intense
flavors and color. The goal is to produce balanced vines which
grow sufficient leaves and canes to support an adequate crop
load. The target crop load is 3 tons per acre which can be
attained through proper pruning, cluster thinning, trellising
and soil nutrition techniques.
The high elevations of mountain vineyards lower both the
daytime peak temperatures and also the night-time temperatures;
the acid and sugar levels in the grapes is kept to an ideal
level.
The Cabernet Sauvignon vines are planted in 8 foot wide rows
running up and down the hillside. The vines are 5 feet apart.
The Merlot vines are planted on terraces that are 10 feet
wide. Those vines are planted 4 feet apart, as the soil has
lower fertility. The Petite Verdot and Cabernet Franc are
also planted on terraces but are 5 feet apart. The rootstock
on most of the vines is 110R but 101-14 is used in some of
the more moderate fertility blocks. The Cabernet Sauvignon
clones are 191 and 337.
Sustainable and organic (non-certified) viticulture practices
are used to nourish the soil and produce balanced vines. Before
the vineyard was planted, extensive soil tests were conducted
to examine the nature of the soil. Test pits showed soil depths
of 2 to 6 feet, over fractured sandstone so the drainage is
good, with low to moderate fertility red loam soil. It was
found that sufficient levels of naturally occurring nitrogen
and potassium exist in the soil, but levels of phosphorus
are low. Small amounts of rock phosphorus and wood ashes are
applied to each vine by hand. The rock phosphorus and ashes
slowly dissolve with the winter rains providing a slow but
steady source of phosphorus to the vines.
Compost is added by hand to the soil to provide additional
minerals, organic material and beneficial bacteria. The bacteria
and other microorganisms break down the naturally occurring
minerals in the soil and make them available to the vines.
Green manure in the form of clover is grown in the rows. In
the spring, the clover is mowed and as the cut clover decays,
it slowly provides nitrogen to the vines.
Regarding
pest control, there has been no spraying for insects at all
since the vineyard was planted 3 years ago. The beneficial
insects, such as spiders and lady bugs, do a terrific job
at keeping the non-beneficial insects, such as leafhoppers
and aphids, at bay. In addition, Western Bluebirds and other
song birds that visit the vineyard help to keep the insect
population down.
With no-till viticulture practices, cover crops are grown
in the rows between the vines to hold the soil in place on
the slopes. Annuals such as barley, annual ryegrass, mustard
and clovers have been planted. Over the years, the cover crops
will be rotated to oats, triticale, cereal rye, bell beans
and blando brome grasses to promote biodiversity. As the vines
mature, discing in the Spring every other row to provide green
manure will be employed. The disced clover will release substantial
amounts of nitrogen to the soil providing nutrition to the
vines and biomass to the soil.