Here at the Extension office, we've offered many classes on growing plants in raised beds. Three methods that I speak of often are square foot gardening, lasagna gardening, and straw bale gardening. I'll quickly outline the three methods:
Square foot gardening is based on 4' by 4' beds (really 4' by you-name-the-length) that are 6" high. What goes in the bed is a 1:1:1 mix by volume of bagged compost, vermiculite, and peat. You then actually make the squares (1' by 1') and plant by the square. This is essentially an instant garden.
Lasagna gardening is making a raised bed layering different organic materials (grass clippings, cardboard, newspapers, compost, straw, etc). You build up layers about 12" to 18" deep and allow it to 'cook'. The height of the raised bed will decrease as the organic materials break down and the worms plow through them. This is not an instant garden.
Straw bale gardening uses a cereal grain straw bale (wheat, rye, barley, etc) that should be 'conditioned' for about 2 weeks, then is ready to plant into. Transplants or seeds can be planted into the bale. Many crops can be raised this way. This is an almost-instant garden.
Raised bed gardens can entail a whole lot more than just these two methods. The main crux is that you are growing plants in a soilless medium. Simply putting a plant into a container is a form of raised bed gardening in a way.
There are several advantages to growing in a raised bed system. Raised bed gardens are better drained most usually than the surrounding area. Raised beds sometimes require less stooping during weeding, watering, and other activities.
Raised beds can also be installed in areas that are difficult to garden conventionally, such as sites with shallow soil (over rock), steep slopes, or poor soil quality.
Some disadvantages of using raised beds is that, depending on what method you choose, these can cost you. The lifetime of a square foot garden (using untreated wood) is about 5 years, so the per year cost is roughly $20 just for the materials to construct it and the medium in the bed. Lasagna gardening is much more cost effective as you are using organic waste products and those are usually free. Square bales only last a year but are fairly cheap. Growing right in your native soil is free as well, except for the tiller wear and tear.
One other potential disadvantage is that raised beds are probably going to dry out rather quickly and will need to be watered more often.
You can plant anything you like in a raised bed. Most vegetables, flowers, and herbs are good choices.
One of the fun things about raised bed gardens is that you can design them any way you want. So if you want a pizza garden, for example, you might want to grow onions, green peppers, banana peppers, tomatoes, basil, marjoram (instead of oregano), and parsley.
A salad garden might contain green peppers, a variety of lettuces, cucumbers, cherry tomatoes, and carrots.
For more information, contact the Pulaski County Extension Service at 606-679-6361 and request the complete publication, Gardening in Small Spaces. We can also send you a publication on straw bale gardening which will outline the recipe used to season the bales. You can also check out books on square foot gardening and lasagna gardening from the Pulaski Co Public Library.
The Pulaski Co Extension office is temporarily limiting public access until further notice. Extension employees are still on the job and can be reached via office phone. Read the entire directive on the Pulaski County Cooperative Extension website at pulaski.ca.uky.edu.
The Lake Cumberland Master Gardeners have pine straw mulch for sale at the Pulaski County Extension office. It is sold in bales for $7 per bale (over 50, $6 per bale). It can be picked up on Tuesdays only.
Learn about timely events or things to do in your home gardens by becoming a fan of Pulaski County Horticulture on Facebook, or following @hortagentbeth on Twitter, kyplants on Instagram, and Pulaski County Horticulture YouTube channel.
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