several other advantages to raised-bed gardening in partially
composted straw bales
Easily accessible beds are 2 to 4 feet
high depending on the number of bales stacked for planting. That
makes them easy to tend from a sitting position.
No tilling and minimal weeds.
After bales are conditioned, the growing
media stays around 85 degrees, giving gardeners a head start on
seed planting and seedling transplants.
The bales can be placed on balconies,
decks or pavement.
Low cost. Bales are less than $10
apiece. Fertilizer costs vary.
Bales can be composted at the end of the
How to start a
straw bale garden
Purchase tight bales of oat or wheat
straw from local farm or nursery supply vendors. Straw is
greatly preferred to hay, which has lots more weed seeds. Tight
bales compost more slowly and provide a longer growing season.
Choose a site with at least six hours of
sun per day during the growing season.
Place several layers of newspaper on the
soil under the bales to prevent weeds from colonizing the bale.
Provide water and a nitrogen source to
start the cooking or composting process.
Bales should be thoroughly watered for
the first three days.
After the initial watering, keep the
straw moist but avoid getting to the point of run-off.
On days 4-6, sprinkle a high-nitrogen
fertilizer over the bale to accelerate cooking. Fertilizer
recommendations vary, but typically ½ cup per day is the
Reduce the fertilizer to Ό cup on days
Once composting begins in earnest, the
bales can reach temperatures up to 105 degrees. Once they cool
to about 85 degrees, they are ready to plant.
Synthetic fertilizers such as urea or
ammonium sulfate can be used as well as organic options like
blood or feather meal. A balanced fertilizer containing
phosphorous and potassium can be added on the final day of
The combination of heat and microbial,
worm and insect activity produces a rich, fertile, organic
medium for roots to thrive. Early spring conditioning gives
gardeners a 30-degree advantage over soil temperatures in late
April and early May, which average 50 degrees in the Pittsburgh
Some gardeners have reported that cooler
than normal spring temperatures may require extra time for the
cooking process to complete. Continue to keep the bales moist
and monitor the internal temperature prior to planting.
Any annual that can be grown in soil will
thrive in bales, including vegetables, herbs and ornamentals.
Summer bulbs and root crops can also be planted in bales,
including the sides. Tomatoes and other vining plants can be
trellised above the bales and row covers and hoops can be used
for season extension. Straw berries can be treated as annuals,
then overwintered and transplanted into new bales.
Seeds or seed tapes, especially for
cool-season crops, can be planted in a tamped-down, 1- to 2-inch
layer of sterile or soilless planting mix with slow-release
fertilizer added. Do not use garden soil as it may introduce
weed seeds or pathogens to the bales.
Seedlings should be removed from pots,
including peat pots, to maximize root growth. Cover all exposed
roots with the sterile mix, and use this mix to fill in the
In the Edible Teaching Garden at 400 N.
Lexington St., Penn State Master Gardeners have grown vegetables
in garden soil and bales. Straw bale plants had two or three
times longer roots, up to 36 inches, than plants in normal beds.
Bales saw reduced weeds and minimal tomato blight and allowed
diverse crops to be intensively planted.
Watering was our major challenge at the
garden site. Our 2016 trial will test two sources of irrigation:
a solar-powered soaker hose system and an ancient low-tech
system of using ollas-embedded, water-filled clay pots.
Allegheny County Master Gardeners will be
hosting a free workshop on straw bale gardening on Monday from 6
to 7 p.m. at the Edible Teaching Garden. Information:
Master Gardeners have used the protocols
detailed by horticulturalist Joel Karsten in his book, Straw
Bale Gardens: The Breakthrough Method for Growing Vegetables
Anywhere, Earlier and with No Weeding and Straw Bale
Gold-colored perennials for shade
Pickling the Harvest