|
Building a Raised Planting Bed with a Surrounding Retaining
Wall
Having a raised planting bed that
rests above the grade of your main lawn for flower or
other planting is an appealing landscape feature. Raised
plant beds offer a three dimensional appeal to your
landscape because of the noticeable transition point
from yard to plant bed. Raised planting beds are often
sought after in high profile landscapes and yard designs.
A raised planting bed has to be contained
so that it will not erode into the yard or into the
rest of your landscape. So, how is this best accomplished?
A retaining wall built around the plant bed will retain
the soil and plantings from being washed away by the
weather. The retaining wall is successive rows of wall
block laid on top of each other to form a wall. The
blocks themselves are made from concrete. If you are
ambitious, you can build a retaining wall for a raised
plant bed yourself. It is not hard, but it involves
a lot of physical labor.
The first thing that must be done when
considering your plant bed and retaining wall is your
plan design. Plan out where the bed will be in your
yard and then get a piece of long rope and layout the
shape of your plant bed on your lawn by laying the rope
on the lawn where you want the plant bed to be.
The best looking raised plant bed and
retaining wall systems are designed such that the retaining
wall top blocks are level from the high point to the
low point. Since the ground where you will lay your
retaining wall blocks is not level and may even slope,
you have to plan your wall design so the top blocks
will be level with each other.
To do this, drive wood stakes in the
ground at the highest and lowest elevation points of
the plant bed dimension. Also drive a stake in the middle
between the high point and low point if you need to
so that your level line will not sag.
Using non-stretch string and a line
level and starting at the high point of your plant bed,
tie the string off to rest where you want the top block
surface height to be. This will be the starting point
of your retaining wall, with the end being the lowest
elevation point. The level line will serve as your height
guide for where the tops of all the wall blocks will
eventually be. Tie the string off at the midpoint and
then the low point, making sure the line is kept level
with your line level.
Following the rope you placed on the
ground for the shape of your plant bed, dig out the
yard grass and sod so that the basic shape of the bed
is formed. Now, using your flat spade or other shovel,
flatten the ground surface nearest the edge of the sod
that remains for the entire length of your plant bed.
This will serve as the foundation for placing your wall
blocks, which have to be level side to side and fore-aft.
Once the ground is relatively flat,
spread 1-2 inches of paver base on the ground surface
starting at the highest elevated point to place your
first wall block. Using a tamper, tamp the paver base
level. Place your first block on top of the paver base
and, using a small level, determine if the block is
level side to side and fore-aft. Adjust the level of
the block with a rubber mallet. The top surface of your
first block should eventually just be touching the string
you tied off to form the level height of your wall.
Spread some more paver base and keep
going with the first row of your retaining wall blocks,
making sure to keep them level individually and from
one adjacent block to the next. Take note that you may
have to do some extra digging to make sure adjacent
blocks are level with one another. Positioning the first
row of blocks to be level is the most difficult part
of this project, but the appearance of the wall will
benefit greatly because of your efforts.
Once the first row of blocks are laid
and are level, you can start on the second row. You
may notice that it will take more blocks on one end
of your wall to be at level height with your guide string
that on the other side of the wall. This is due to the
grade of your lawn. Keep adding additional blocks onto
the first row, until the second row is completed. Since
your first row of blocks is level, so should your second
and third rows be.
Lay the rows of blocks until your final
wall height is reached determined either by the relative
distance from the guide string or just by your visual
judgement. It is fine to add partial rows to be on the
top of the wall instead of ending the wall with one
contiguous row. It just depends on your personal preference.
When your wall is completed, the top
of the wall will be higher than the ground where you
first started. Now take some pea gravel and pour it
around the base of the wall on the inside of the plant
bed to promote proper drainage. Start to backfill the
plant bed with the soil of your choice, possibly adding
more layers of pea gravel against the wall or other
edges of the bed for proper drainage.
Once you have completely filled the
plant bed with the soil, you are done, and are now ready
to add plants and flowers of your liking.
1howto.com
--------------------------------------------------
Please
Share Your Tips with Us
|
