The hardest part of straw bale gardening may be finding the straw.
"I've talked to lots of feed stores; they can't keep the bales in stock," said author Joel Karsten. "Everybody wants them for gardens."
From his Minnesota home base, Karsten has become the nation's straw bale gardening guru.
His new book "Straw Bale Gardens: The Breakthrough Method for Growing Vegetables Anywhere, Earlier and With No Weeding" (Cool Springs Press, 144 pages, $19.99) debuted this spring and immediately hit Amazon's list of best- selling garden books.
"I've been doing this for 20 years," said Karsten, who was initially inspired by straw bales on his family's farm. "For the first 14, I couldn't get anybody to care about it no matter what I did. But in the past six years, it's just exploded.
"People see it and they're fascinated by it."
That includes us. We're trying a couple of straw bale gardens this summer. (See our SacBee Garden page on Facebook for updates on their progress: www.facebook.com/SacBeeGarden.)
Straw bales caught on along with renewed interest in vegetable gardening. They're basically a form of raised-bed gardening, but without the expense of constructing conventional beds.
For home gardeners, they have several potential pluses: Straw bales offer a fresh growing medium each year, which means no lingering disease or pests. They don't need soil, either.
"On our Facebook page, you can see them growing in parking lots, right on the asphalt," Karsten said in a phone interview. "You could do one on a rooftop."
In colder climates, straw bales allow gardeners to plant summer vegetables earlier because the straw releases heat as it decomposes, warming the roots of young transplants and seedlings. That's also a plus for winter gardens in Sacramento, where straw bales can be used year round.
Karsten explained with a chuckle one big advantage straw bales have over other growing mediums: "No weeding, no weeding, no weeding.
"For most people, that tops the list of what they're looking for in a perfect vegetable garden."
Weeds defeat many gardens especially for newbie vegetable gardeners.
"With straw bales, it's impossible to fail," Karsten said, "if you follow directions."
There's the catch you can't just poke your potatoes into the bale and expect them to flourish.
Straw bales need a little TLC before they become dynamic garden beds.
"No. 1 thing to remember: Start with straw, not hay," Karsten said. "That seems elementary, but it's not obvious especially if you're not familiar with straw."
Hay is harvested while still green and full of grain (which will sprout or rot if used in gardening).
A byproduct of grain farming, straw the leftover dried stalks is meant for animal bedding or mulching, not food. Sacramento straw comes primarily from rice or oats.
"Straw bales must be well conditioned for gardening," Karsten continued. "You can't just plant plants in a bale without treating it beforehand. Anything you plant in plain straw will die."
The conditioning process takes 12 to 14 days. During that time, the bale needs to be watered every day. That aids the internal-composting process.
Straw's ability to hold water is another benefit for gardeners. It keeps plants' roots evenly moist.
"A saturated bale holds six to eight gallons of water," Karsten said. "It's impossible to drown a bale, too. The excess runs out."
Once conditioned, the bales become a high-yield, nurturing environment, perfect for many summer vegetables.
"You'll never grow better tomatoes," he said. "Strawberries and melons are great. Potatoes can do exceptionally, too. And they're so easy to harvest just cut the strings and knock over the bale."
Call The Bee's Debbie Arrington, (916) 321-1075. Follow her on Twitter @debarrington.