Intensive, or "double dug" raised bed gardening
yields the most produce for the least area of any
realistic gardening method. Originally developed
for use in narrow back yards in France, these
raised beds require little annual upkeep and no
power tools to continue in production.
concept of French Intensive gardening is that
raised beds are created which have humus added, and
the whole bed is light and fluffy to a depth of two
feet to promote fantastic root growth. The beds are
typically 5 or 6 feet wide and 12 or more feet
long, with 3 foot paths between the beds. Each bed
is a low mound in shape, and if desired boards can
be placed along the sides to maintain a distinct
border, but that is not required.
develops the concept that gardening in the
new Millennium may be very different, and
presents plans on survival gardening, maximum
yield of edibles per area, how to make a
"French Intensive" garden as well as an
all-year vegetable garden. Order
created in a separate bed from chopped yard debris,
grass clippings, manure (except horse manure), and
kitchen scraps, then added as a top dressing every
Establishing a raised double-dug bed is neither
easy nor fun, and it takes a year before the bed is
highly productive. Typically, a row is dug on the
long axis of the bed using a shovel, then a heavy
duty garden fork is used to break up the clods, a
layer of humus added, and the trench dug deeper and
added to the pile. This process is repeated
backwards along the bed, during which the soil is
thoroughly mixed with the humus and/or compost and
broken up into fine particles.
heavy clay soil is very difficult to initially dig,
whereas a sandy loam is much easier. Heavy clay
soils can be improved considerably by adding a lot
of sawdust and mason's sand. DO NOT use beach or
river sand! Mason's sand, being crushed granite,
has sharp edges and actually loosens the
A lot of
sawdust or wood chips, chopped straw, chopped
leaves (except Walnut), etc, make a heavy clay soil
lighter and more friable, but also consume nitrogen
as they decompose. A cup of ammonium nitrate per 10
feet of row replaces the lost nitrogen.
excellent soil amendment is vermiculite, which can
be purchased relatively inexpensively from concrete
suppliers. Vermiculite is basically puffed granite
particles, so it holds moisture extremely well and
is not biodegradable.
established, French Intensive beds require little
additional work, and their main limiting factors in
producing high yields are sunlight and water.
Because the beds are densely planted they are
effectively interplanted,* so plant spacing is
important, and growing similar height plants next
to one another is a good idea.
require about 1 inches of irrigation water per
week, and French Intensive beds require no less.
This can be "grey" water, misted sprayers,
whatever, but should be applied until the surface
of the ground is "shiny" for a few seconds.
Frequent light watering does not encourage the
water to penetrate to a great depth, yet with 2
foot deep beds to encourage deep root growth, deep
watering of French Intensive beds is
French Intensive beds is a unique experience.
Instead of a single long row as in "normal"
gardening, the rows should be at least a foot to 3
feet wide and run across the bed. Now you can see
why the paths should be about 3 feet wide: you have
to kneel on the path to plant to the middle of the
bed, then go to the other side, kneel, and finish
planting the "row."
plant "spacing" in normal gardening is accomplished
by thinning the rows. In French Intensive gardening
the spacing is accomplished by seeding at the
correct space while planting. See the "thin to"
guide in this booklet, or look at the
recommendations on the seed packet itself for
One of the
least understood aspects of gardening is that of
capillary action of the garden soil. It is a proven
fact that compressed earth has a better capillary
action than undisturbed soil. That is why gardening
books tell you never to walk between rows in a
regular garden, as that encourages weed growth. And
of course people are told never to step in a French
Intensive bed and thus compress the
capillary action is absolutely necessary to bring
water up to the roots of growing plants to promote
good and deep root growth. In regular garden rows,
it is easy to roll a heavy 2 or 3 inch wide
weighted wheel (mounted on an axle and handle) down
the row directly over the freshly planted seeds,
which will then promote deep root growth along that
line. The spaces between the rows are than
rototilled to eliminate footprints prior to the
Intensive gardening, the compressing of the soil
directly around the seed can be done using a 2 inch
round object such as a water glass. The seed is
planted, then the glass (or whatever) placed over
that spot and the soil compressed an inch or so.
The now-compacted soil will draw moisture up
directly beneath the seed, and the roots will be
encouraged to grow straight down and
*INTERPLANTING: Many of the
fast-maturing vegetables (leaf lettuce, mustard
greens, spinach) may be planted among the seedlings
of slow-growing vegetables (peppers, eggplants, or