Over the Garden Gate: Making it grow in a straw container

Straw bale gardening is container gardening using bales of straw as the container. This type of gardening would be a great option for areas with poor soil conditions or limited gardening space. It would also work well for someone with limited mobility.

Items needed to begin straw bale gardening are straw bales, nitrogen-rich fertilizer, plenty of water and hand trowel. Additional items you could incorporate are a weed barrier (newspaper or cardboard will do) and supports such as steel fence posts and wire. Mulch can be used if you desire.

Deciding where to place your garden is your first big decision. You’ll need a location that receives as least six hours of direct sunlight daily and easy access to water. Otherwise, since you are not actually “digging in the dirt,” you can place your straw bale garden just about anywhere. For example, a straw bale garden can go alongside of your house, in a vacant lot, on a patio or bordering your driveway.

If you are going to place bales directly on a lawn or bare soil, it is best to place a weed barrier down first. This could be four- to five-sheets thick of newspaper, or you could use cardboard. Place the barrier under the bales leaving at least several inches sticking out around the bales. This will help keep grass and weed growth away from the bottom of your bales. Place your bales so the twine is on the side and the cut side of the bale is facing upward.

Once you have found a location where your bales will receive at least six hours of full sun, you will be ready to begin straw bale gardening.

Getting started: Purchase straw, not hay. This purchase can be directly from a farmer or a farm supply/gardening store. Decide what type of fertilizer you want to use for conditioning your bales. You need a high-nitrogen fertilizer, such as urea (46-0-0) or, if you choose a more organic approach, fish or bone meal.

Next, you will be ready to condition your bales in preparation for planting. You should allow around two weeks for this process.

Here is a general process for conditioning:

On the first three days, water the bales thoroughly so that they stay damp. On days 4 through 9, water with an application of your nitrogen-rich liquid or powdered fertilizer, mixed in a watering can. This might be urea, or organic fish or bone meal.

This will accelerate the decomposition process. Start with ½ cup of urea and reduce to ¼ cup in later days. For an organic, start with 3 cups and reduce to 1-1/2 cups in later days.

Conditioning will cause the bales to heat up to around 120 degrees or higher inside, composting the bales internally. Use a compost or meat thermometer to check.

On day 10, apply a 10-10-10 (nitrogen-phosphorus-potassium) all-purpose fertilizer. Let your bales rest on day 11, but feel the top and check your thermometer. Wait until the temperature of the bales reaches outdoor temperature. Then they are ready for planting.

Planting: To plant transplants, dig a hole on top of the bale, loosen transplant roots and place transplant in the hole, place some potting mix around the plant roots. Note: Do not use soil for this since you would just be inviting weeds, soil-borne diseases or pathogens into your garden.

To plant seeds, mound up and work sterile planting mix into the top of your bale to make a 1- to 2-inch flat layer on the bale. This layer is just a place to start your seed. The seedlings will root and eventually grow into the straw bale.

Most plants grow well in straw bale. Some suggestions include tomatoes, cucumbers, peppers, pumpkins, squash, potatoes, beans and lettuce. Basically, almost anything you would like to grow will work. One exception is corn, which has huge roots so you could only grow two stalks in each bale of straw.

Watering and fertilizing: A straw bale garden will require consistent watering to make sure bales remain damp. Bales will also need to be fertilized with a water-soluble fertilizer every few weeks.

End of the season: Straw bales will last for one or at most two growing seasons. Once your crops have been harvested, the bales can be left alone to compost on their own, or placed in your compost pile. You will have excellent compost to place around your plantings next season and can start all over again with new straw bales.

If you have any gardening questions, email (with photos if necessary) to beavermg@psu.edu. Garden Hotline volunteers are working during stay-at-home guidelines to research and provide answers needed for home gardens.

Hedy Pflug is a Master Gardener Intern with Penn State Extension -- Beaver County.