Grow bags can be a great solution for gardeners with limited space. However, grow bags have many benefits that are available to all gardeners. I will answer your gardening questions in this week’s show, including the benefits and challenges of using grow bags. Recently, we asked our followers on social media what they wanted to know about Grow Bag and wow we received a lot of questions. All of the answers are included in this podcast.
Although I have 16 raised beds that are big, I added grow bags to the setup. In this post, I’ll explain why they are convenient and useful. I like experimenting with my garden and trying new things beyond what grows in my raised beds. Grow bags, and mini-raised gardens that pop up like pop-ups, allow me to add temporary growing space. Once I’m done with the space, I can put the bags in storage.
Grow bags can be useful to all gardeners, but urban and small-space gardeners will benefit the most. Grow bags work well for gardening on decks, patios or a stairway.
Choose the Best Grow Bags
Heavy-duty landscape fabrics, usually polypropylene, are the best choice for growing bags. Material is usually food-grade and free from harmful substances. Polyethylene is another common material for landscape fabrics. It is made from recycled plastic bottles. The best fabric for landscapes is a spun-bond, no matter what the material.
What you pay for is what you get. You won’t find the best bags if you only shop online based on cost. Some bags don’t come with handles. These are important because they allow the bag to be moved around. However, not all handles work equally. Amy discovered that the handles of cheaper grow bags fell apart within a season. She suggests looking for bags with handles that are sewn into the bag and not sewn on the outside.
Consider the reputation of both the seller and the manufacturer. I like Root Pouch Smart Pots and Spring Pots. There’s no way to go wrong with these brands. You can also shop around and experiment until you find one you like.
Whatever material you use, UV light, heat, water and other environmental factors will break it down. Burlap or cotton can be used to make your own grow bags, but you should consider durability, strength, and longevity. You will be lifting the bags when they are filled and moving them around. They will need strong handles and extra-strong seams.
Growing Bags Benefits
- Extra space when you need it: If I plant a slow-growing crop in my raised bed gardens, my chances of succession plantings are limited. Add grow bags to my garden and I can expand the possibilities. You can choose from a variety of sizes to find the right grow bag for your needs.
- Easy Harvesting Growing bags are convenient for harvesting roots. You don’t need to use a garden fork when harvesting sweet potatoes and new potatoes. This could damage the tubers. I use a sifter to pour out the bags so that 100 percent of the underground growth remains intact. The soil can then be saved and re-used. Some bags come with flaps that allow you to take out only the tubers needed for dinner.
- Attract pollinators: You can scatter grow bags around your garden to attract pollinators and add color. Plant flowers in the bags. You can move the bags by lifting them up with their handles, or putting them on rollers.
- Crop rotation: I have 16 raised beds and grow many plants that belong to the same family. It is difficult for me to rotate my crops. Crops should rotate every four years, from one bed into another before returning to the original bed. My raised beds have become infested with soil-borne pathogens. It’s not about if, but rather when, you won’t be able to rotate your beds enough. Grow bags are the perfect solution for me to find new locations to grow tomato and chili, both of which belong to the nightshade group. It saves me the cost of building new beds. Compared to wood, grow bags are relatively inexpensive. Fill them with soil that is free of any pathogens.
Amy can attest to the advantages of using clean soil in grow bags. She tried grow bags and potting soil after struggling with tomato and bell pepper diseases, and poor growth. She reported that the plants had more bushiness, more fruit and less disease. The soil was also likely to have more nutrients, in addition to being pathogen-free. Amy says that the experience made her more aware of soil issues in her garden.
Plastic Containers vs. Grow Bags Plastic Containers
Belinda, a podcast listener, wanted to know whether she should use growbags when she has already had success using plastic containers. I believe that you shouldn’t change something if it’s not broken. You may get better results with grow bags.
The roots of a plant growing in a rigid container and one in a growbag behave differently. When the roots reach the edges of a rigid plastic container, they continue to grow, but are forced to grow in circular patterns. The plants will become “pot bound” and “root bound”, which limits their access to nutrients and water. This condition, which can be fatal for plants that stay in pots for a long period of time, such as shrubs, will eventually cause the plant to die. Annuals and seasonal crops are less at risk.
The roots stop growing when they reach the edge. The bags are porous and allow air to pass through. The roots stop growing when they reach the air. Air pruning is the process of preventing roots from growing in a certain direction.
What Size Grow Bag is Right for You?
Many of my listeners asked me what size grow bag I recommended for each crop. Not only the volume, but also the dimensions of the bag are important. Some bags are wider than they are deep, and vice-versa.
You can use a shallow and wide grow bag for plants with shallow roots, such as onions, lettuce and garlic. For deep-rooted plants such as carrots, parsnips tomatoes, peppers Brussels sprouts and other vegetables, you will need a larger bag.
In addition to being aware of height and width, it is important that I select bags with a minimum volume of 5 gallons. Smaller sizes do not have enough space for a sufficient root mass. I want to provide my plants with every opportunity to grow. If my plants want to develop a large root system that will support their top growth then I’ll give them the space to do so.
Minimum 5 gallons of water per large plant. But I would not grow two indeterminate tomato plants in the same bag, whether it is a 10-gallon or a 15-gallon one. When you grow a plant that has a large root system, it will compete with other plants in the bag. You can combine a tomato and a shallow-rooted plant in a large bag instead of two tomatoes.
Budget concerns arise when larger bags are used. The cost of larger bags is higher, and it costs more to fill the bags with soil. Consider this when making your purchase. If you are only growing one head of lettuce, or just a single cabbage, or a few spinach sprigs, then a smaller bag will suffice.
Amy used a grow bag of 25 gallons, which is about the size of a medium raised garden bed. She used the space efficiently by planting a tomato and onions in the middle. The downside is that it costs a lot to fill the bag with soil. Once a 25-gallon grow bag is full and in place, it can be difficult to move. The 25-gallon bag is ideal for growing sweet potatoes or a small tree that will be moved inside during the winter
Where To Place Grow Bags?
My students from my master seed starting class wanted to know which surface to use to grow bags. Sherry noticed that tomatoes placed in bags on her deck didn’t do as well.
Surface does matter. On a surface with a rough texture, the bags received water only from the rain and Sherry. The bags on the lawn had the chance to absorb moisture from the ground.
Staining is another issue when you have a solid surface like a patio or driveway. You will get a dirty ring from the bag, but a liner can be placed underneath to protect the surface. The bag can also be propped up on bricks. However, the bottom will be exposed which will cause the root mass to dry out faster. You will need to water your plants more frequently.
What soil should be used in grow bags?
Grow bags need a soil that drains well and retains enough moisture to prevent the roots from drying out between waterings. Bagged products labeled potting soil or container mixture are ideal.
Several potting soils include peat moss, but increasingly more are using coconut fiber (coir) in place of this. Perlite is those white beads which look like styrofoam. Perlite is a mineral which retains moisture, making potting mix lighter. Vermiculite is another option. It’s flaky and has the same function as perlite.
Wood fines and forest products are also included in bagged mixes. These are just finely ground wood.
It is not necessary to replace your soil every year, unless you have soil-borne disease infected the soil. Investigate the disease that affected the plants. You will find out if they are soil-borne. You can also have your soil tested at the local extension office for pathogens.
You can use the clean soil for another year by pouring it into a wheelbarrow, or a large container where it can expand. Add compost after removing any clumps of soil or roots. Compost should be added to the soil in amounts of about 25% of its original volume. Compost will provide plants with the microbiology and nutrients they need to thrive. You can also use organic slow-release fertilizer.
Many people ask me about planting straight compost. Although compost can produce great results, it does not contain all the nutrients plants require. Although compost is a diverse mix, plants need minerals and nutrients in greater quantities. You can amend your compost with wood fines, perlite/vermiculite and lime to create a more potent container mix.
Watering Grow Bags
Grow bags are prone to drying out quickly. You can’t keep up without a irrigation system. Assembly is easy with these systems. You’ll also get a battery-powered timer. This is a great way to ensure that your plants receive the water they require.
Apply 2 inches of organic material, such as straw or shredded leaves, to help retain moisture in the soil. Mulch can also be used to suppress weeds and provides nutrients and organic matter for the soil and plants.
Grow Bags and pests
Grow bags do not have more pest problems than raised beds. There may even be less pest problems because pets have a harder time getting in. Follow the same integrated pest control practices as you would in any other part of the garden if you find pests.
You can open the flaps of some grow bags to harvest or check root crops. You may find ants, or other insects inside the bag when you open the flap.
In the garden, ants are not a big problem (unless they’re fire ants). The common ants are good for the soil, but they don’t really pose a problem. I do not recommend that you intervene to control ants.
How to Use Grow Bags during Winter?
You can store your grow bags until spring by emptying them of soil before winter, folding them flat, and sanitizing them. You can also leave the bags in place, with soil inside them, for the winter.
Grow bags can be used to overwinter some crops. Annette, from Beginning Gardener Fundamentals, plans to store her potatoes in grow bags for the winter so that she can remove them as needed. Carrots are also great for storing in cold weather. They can be left out.
Most crops find it difficult to overwinter in grow bags. Because the entire root mass is elevated above ground, roots are more susceptible to cold. In-ground or raised bed gardening is better for overwintered crops.
If you plan to store empty bags over the winter in a storage unit, first give them a thorough rinse with a garden hose and then dip them into soapy water. You can put them into your washing machine using cold water but not in the dryer. Allow them to dry naturally. Once the clothes are completely dried, you can pack them away.
Grow Bags with Sunlight
Vegetables require full sunlight: six to eight hours of direct sun per day. Some gardeners rotate their containers or grow bags each day in order to get the sun out and avoid the shade.
Cindy, a member of the Facebook group joegardener, moves her growbags around on platforms that have wheels. She can’t keep up with such a demanding task. Plants don’t require us to be perfect. There are often cloudy days in nature. Your plants will survive if you leave them in the shade once or twice per week for a half-day. Do the best that you can, and don’t worry about it.
Use Supports for Grow Bags
Don’t overthink the process of growing plants which require support. Don’t fret if a tomato cage punctures holes in the grow bag bottom. Bags are porous, so even a few small holes will not affect the integrity of them.
If you want to use a cage larger than the bag, it may be necessary to make one yourself. For example, a concrete reinforced wire cage. You can also drive stakes around the bag’s perimeter into the ground.
Add Fertilizer To Grow Bags
Over time, nutrients and supplemental fertilizer may leach from grow bags. However, there are ways to reduce this concern.
I make sure to use organic liquid fertilizer regularly, whether it is a soluble liquid — one that dissolves in water and comes in dry form — or if it’s sold in liquid, then diluted like . The plants get the nutrients they require from the supplemental fertilizer I use and the compost that is bound to the soil
What Can Grow In A Grow Bag
Many listeners wanted to know what plants were best suited for grow bags. You can grow any crop that can be grown in a raised bed or container in a growbag. The plants will thrive if you place them in a well-drained environment with the correct soil, and water it correctly. That being said, I would recommend choosing plants that reach maturity quickly. The risk is lower over a shorter growing period.
Black Vs. Grow Bags in Color
Mark, a student in my Beginning Gardner Fundamentals class, wonders whether the color of the grow bags matters. Black is easier to find, but other colors are available, including some that will blend into the garden, and others in vibrant green or blue.
When choosing colored bags, the main consideration is how much light can pass through. Avoid light-colored bags that are thin. Roots do not want to be exposed. If the material is thick, it doesn’t really matter what color the bag is.
I like bags that are darker in color because they absorb more warmth. The heat retained will help protect the roots during cold nights, and result in more productive plants.
Use Grow Bags to Space Plants
Cindy, a member of the Joegardener group on Facebook, points out that most plant spacing guidelines are based around a square.
