Containers can be tricky. They’re invaluable for those who don’t have garden space or whose soil is extremely poor. Even if you have space, there are areas where the soil is so poor or laden with heavy metals from historic mining or industrial use that you wouldn’t want to eat anything grown in it. Containers are the way to go in either situation.
Most people grab plastic or even clay pots to remedy the problem, yet they tend to overheat, dry out and compress the roots, making the plants less productive. But I’m confident I found the remedy for all three issues.
Grow bags at a glance
Compared to growing plants in plastic and clay pots, the vegetation you plant in grow bags does not get rootbound. The roots are naturally air-pruned.
The roots stay cooler in grow bags, and the overall cooler soil temperature keeps beneficial microorganisms thriving.
The grow bags are lightweight and easy to move around in case needed. This allows you to extend the growing season by moving your plants to a sheltered location or a more friendly environment.
Using grow bags above ground level allows you to better combat pest problems.
You don’t have to worry about overwatering as you do in containers. Using the water tray provides water to the roots as needed and saves time.
Grow bags are easy to sore, and this makes them ideal for stockpiling in your bug-out location.
Success story involving growing bags
I had never been a container person, but I thought it was worth giving the bags a try when a friend beat a flea beetle problem by growing his eggplants in containers roughly a foot off the ground. I started researching container options and decided that the polypropylene fabric grow bags sounded like the best option.
Personally, I was sold on them the first season. I had never had much luck with eggplants, but once my two plants in a single grow bag were established, they took off. My plants got 3 feet tall, and I got very excited when those big pink/purple blossoms came out was excited.
One plant produced three eggplants, and the other gave me nine beautiful fruits. Even though the flea beetles eventually did find my plants, they were large enough to withstand the attack. Since my initial eggplant experiment, I’ve also tried cucumbers, which thrive in the conditions, as well as potatoes.
Why grow bags are a favorite of mine
Compared to pots, a good grow bag releases up to 30 degrees Fahrenheit more heat than traditional plastic. This allows the containers to stay cooler, and the roots can grow in hotter temperatures and keep microorganisms alive and working inside bags.
This heat distribution can’t be overemphasized because if you have heat on your roots, you will not have produce.
To obtain healthy plants and produce a successful yield, you should buy the proper grow bags made from a two-layer fabric that is both breathable and allows for good drainage. Plants’ roots won’t circle like they do in a pot or container. They will grow to the edge and are air pruned. When that happens, the roots branch, making a more extensive root system.
Air pruning is especially important if you’re going to raise perennial crops, such as blueberries (since blueberries will not tolerate our alkaline soil, the only way to grow them around here is in a controlled container) because they won’t become root-bound.
Even tomatoes and other vigorous annual vegetables send out tremendous root growth. By using the fabric bag, you are helping create a far healthier foundation for the plant.
As for soil, I recommend keeping the soil on the lighter side, just as you do in other types of containers. I have amended my soil for decades, and I use my own mix. I usually fill the bags with a mix of some decaying straw and soil that I took from the bottom of the ‘cold’ compost pile.
Other times, I add a few scoops of my rich garden soil. If you don’t have compost-like garden soil at home, you can create your mix or use good-quality soil geared towards containers. Many people use commercial container mix, which is created with compost, sphagnum peat moss, and vermiculite to provide good tilth and nutrients.
Bag sizes and shapes
One of the best features of grow bags is the range of sizes. There are grow bags holding 120 quarts of potting soil and are 25 inches in diameter. This opens up a world of possibilities for what you can grow. Honestly, from corn to sweet potatoes, I can’t think of anything you can’t grow in such a bag.
I planted two eggplants, five cucumbers, and two Roma tomatoes in each of my grow bags. These were supplements to my already extensive garden, demonstrating how people with plenty of in-ground garden space can benefit.
If you live in an apartment or have a tiny backyard, the bags can provide plenty of gardening opportunities. To make the possibilities even more enticing, a friend living in the city introduced me to the many options now offered.
I was delighted to find out there are grow bags designed specifically for tomatoes (which are deeper to accommodate the tap root), tall ones for potatoes, as well as different sizes and depths for peppers, carrots, and garlic.
I also prefer the smaller bags to grow my herbs since I can bring them inside at the end of the season. I sow the herb seeds in them towards the end of the season. If foul weather threatens the tender plants, I move the grow bags indoors. When the sun comes out and temperatures warm, I simply take them back outside.
An accessory to grow bags that is immensely helpful, particularly to those of us who seem to do nothing but water during the summer, is the self-watering tray. It’s a plastic-bottomed reservoir that you fill with water, and a fiber mat pulls the water from the tray.
Pulling water from the roots is the ideal way to water, and the self-watering tray gives people the latitude to leave for a couple of days without coming home to dehydrated vegetables.
When using the tray, the only thing you have to do is cut a little hole where the notch is in the plastic top of the support so you can pour water into the tray. Pour enough in to soak the mat, then add more to top off the level in the tray. After three to four days, check the water level again.
For me, watering the grow bags in my garden has never been a huge issue. I’m so used to not having to water, and I tend to forget about it. The only way I know to water is if the plants don’t look so hot. During the summer, I might haul a gallon of water out a couple of times over a month if it’s excessively dry.
As far as watering goes, you don’t have to worry about oversaturating your plants as you do with plastic or clay containers. Many of us were taught to put gravel in the bottom of a container to provide drainage; in reality, we just create a dead zone for the roots and open up the possibility of rot.
Grow bags don’t do that, allowing every inch of space to be used. As I do with any garden bed, I recommend mulching around the plants in the grow bag. Straw is an easy and fairly inexpensive option that keeps moisture in the soil and maintains a more temperate soil temperature.
Since the grow bags do such a good job of dispersing heat, it’s a shame to have the top layer heat up and destroy your efforts.
I recommend dumping the soil out of grow bags at the end of the season and bringing them indoors. They’ll last three to five seasons. To clean them, just wash them out with a hose or in the sink, allow them to dry, and fold them to store. They don’t take up much space. You don’t have to store them if you have perennial crops or if you wish to plant cover crops in them.
I even planted alfalfa as a green manure crop in my grow bags. It fixes nitrogen into the soil and provides additional organic matter. In the spring, I’ll turn it under the soil before planting.
After being left out for four winters, my bags still look good as new. Grow bags are equally valuable for fall crops, particularly since you can bring the plants onto a porch or pull them into the garage on those early chilly nights. So many times, we’ve had a September freeze that nipped everything in the garden, only to warm up to ideal growing conditions for several more weeks. When the plants are in the portable bag, you can stay a step ahead of the weather to harvest well into the autumn season.
Using fabric grow bags is one way for gardeners with limited space or sub-standard soil to grow anything they want. They are portable, last for years, and are practical.
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