No garden space? No problem! Grow bags are an easy way to garden anywhere! Learn why grow bags are better than pots, and how to use them for the best results!
Did you know you can grow a vegetable garden in a bag? Growing plants in a bag may seem odd, but it provides several advantages. I'm going to share these secrets with you today!
In this article, we take an in-depth look at using grow bags for gardening. What are they, and how are they different from other containers? What are the advantages and disadvantages?
Let's get started!
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Why Use Grow Bags?
Let's start with this simple question: why would I grow something in a bag instead of a plastic or terracotta pot?
At first glance, it may seem counterintuitive; however, I think you'll soon see what a great tool grow bags can be.
Air Pruning the Roots
The largest appeal for using grow bags is their ability to prevent roots from binding. If you've ever removed a plant from a pot and found huge swirls of roots at the bottom, you'll know what I mean!
A plant becomes root bound when it outgrows the pot. The roots are looking for a place to go, and they start to grow in circles around the inside of the pot. This thick tangle of roots doesn't allow the plant to absorb nutrients from the soil effectively, so it doesn't grow as well as it should.
So, to prevent your roots from becoming bound, it would make sense to prune your roots. While there are some techniques to prune roots, you run the risk of cutting the wrong one and stunting your plant's growth (or even killing it!)
Grow bags allow air to penetrate the exterior of the soil. As the roots grow toward the edge, they will contact the air and stop growing in that direction (this is why you normally don't see roots at the top of the soil). This "air pruning" signals to the plant that it should grow more roots that branch from the center.
So, not only do grow bags prevent roots from becoming bound, but they also encourage new root growth, resulting in a healthier plant!
Grow bags are typically cheaper than pots. You can get a pack of 5 five-gallon grow bags for under $20. I recently bought an assortment of different sizes for the outdoor plant stand I'm building for our deck, and it cost a fraction of the price of individual plastic pots!
Depending on where you shop, you could probably find even cheaper options. Some people have even had success with fabric Walmart bags! Anything that allows for proper drainage and soil-to-air contact along the sides will work.
Hard pots tend to hold in the heat, especially when they're a dark color or made of stone or concrete. If you live in a particularly hot climate, you could roast your plant!
Grow bags allow the plants to breathe. Think of grow bags as having the ability to sweat, allowing for superior thermal regulation.
You don't need to worry about drowning your plants when using grow bags. The porous nature of the fabric allows water to drain out, so you don't get root rot.
Storage and Mobility
Many folks living in apartments feel left out of the gardening club. Not anymore! With grow bags, you can have a substantial amount of plants on your balcony or patio. What do you do with all those bags in the winter? Simply fold them up and store them away!
This also makes it easy to pot up plants as they grow. Instead of storing a huge variety of containers and trays, you can buy an assortment of seedling grow bags that take up very little space.
For those who have plenty of space, grow bags are simple to move around, as they usually have handles attached. As the sun patterns change throughout the season, you can move your plants to sunnier or shadier spots as needed without worrying about dropping a heavy pot.
Not all plants need the same kind of soil. With grow bags, you don't need to trade off one plant's nutritional needs for the others.
Some will thrive in more acidic soil, or need more nitrogen, phosphorous or potassium than normal. You can also experiment with different types of fertilizer on the same kind of plant in different bags to see what works best!
The portability of a grow bag allows you to plant a garden in places that would otherwise be off-limits.
I've even grown tomatoes in grow bags! Build this simple DIY tomato cage that fits perfectly around a 10 gallon grow bag to support the plant as it gets bigger.
If you're renting a house, your landlord may be more friendly to setting up a large grow bag rather than digging into the yard or building a raised bed. When you move, you can take your garden with you!
Drawbacks to Using Grow Bags
Alright, we've discussed the positives, now let's explore the negatives. While grow bags are a great asset, they aren't perfect.
By themselves, grow bags aren't as easy on the eyes when compared with a beautiful garden pot. While they now come in a variety of colors, I prefer the black ones because they don't show dirt and water stains through the fabric.
Building a wooden frame around your grow bags can help keep your yard looking beautiful while still enjoying the benefits of these containers. For example, this planter box with a trellis would be perfect for a climbing plant like tomatoes or peas! Just pop a grow bag into the box and watch it grow!
This DIY outdoor plant stand features planter boxes to hide larger grow bags, plus shelves for smaller ones.
You could even build a raised bed frame, but fill it with individual grow bags instead! This would make it much easier to replace plants as growing seasons change, while also hiding the unattractive fabric.
Needs More Water
While the grow bag's ability to drain water is a plus, it can also create some extra work. Since water easily drains through the fabric, some plants will require more frequent watering.
Thankfully, there's an easy fix! Set up a drip irrigation system to water all your plants on their own schedule!
Drip irrigation is easy to set up with your existing outdoor faucet and flexible rubber tubing. Individual emitters in each bag allow you to customize the amount of water each plant receives. Then add a timer system so you can set it and forget it!
You can also create a water reservoir to place under your grow bags. Some people even use a kid's swim pool! As long as you keep the pool filled with a few inches of water, the plants will draw up the moisture through the bottom as needed.
Grow bags can be less durable than other options. Over time, the fabric can degrade, rendering them ineffective. Also, if you have an especially large and heavy bag, there's a possibility it could rip when you try to drag or move it.
All these problems could end up costing you more money in the long run. However, grow bags can last quite a while. Here are some things you can do to make your grow bags last.
First, buy quality - if you plan on using them for a while, it's worth the extra cash. While a reusable cloth bag from the grocery store may work in a pinch, it's not going to survive as long as a grow bag that was specifically made for this purpose.
Second, empty them for the season. Having soil in your grow bag year-round will cause your grow bags to wear faster. Dump the used soil in the compost bin and have it ready for the next round in the spring!
How to Use Grow Bags
Growing flowers or vegetables in grow bags is just like any other container. There are some things you want to take into consideration as you sow your seeds or plant your transplants.
Consider the Size of Your Plant when Fully Grown
You don't want your plant to outgrow your pot. Make sure you have the best-sized pot for your plant at the start, to save yourself the trouble of repotting and reduce transplant shock.
Grow bags are typically sold in a variety of gallon sizes. I picked up a pack of 2-gallon, 5-gallon and 10-gallon bags for my vegetable garden. You can see the difference in sizes below.
Here are some guidelines for the most common vegetables:
- Tomatoes - 5-10 gallons (full-size), 3-5 gallons (cherry)
- Beans - 3 to 5 gallons.
- Cucumbers - 4 to 5 gallons (less for dwarf)
- Carrots - 1 quart to 3 gallons, 12 inches deep
Use Potting Soil
Make sure to use potting soil instead of garden soil. Garden soil contains a bland mix of sand and dirt that is made to supplement your existing topsoil. While this works well for your yard, it isn't ideal for pots or bags.
Instead, use good potting soil. Some varieties have fertilizer mixed in already, so you'll need to take that into account when adding fertilizer yourself. Too much can burn your tender plants!
By the way, the DIY potting bench you see in the photo above has gotten a ton of use this spring! It really saves my back and makes it much easier to pot up these plants. It also keeps the potting soil and fertilizer all in one place on the shelf below, so I can quickly get to work!
Check the needs of your plant, and then add a fertilizer that gives it what it needs. Plants in pots or bags need a little extra boost, as daily watering will begin to wash away needed nutrients.
I prefer to use organic fertilizer in my vegetable garden, so I added some Espoma GardenTone to my potting soil before planting. For tomatoes, I use Espoma TomatoTone, which has the exact nutrients they need for a huge harvest!
Add Vermiculite to Retain Moisture
Grow bags will require more water than the ground or a regular pot. By adding vermiculite to your potting soil, you increase your soil's ability to retain water. Keep in mind that many potting soil mixes already include vermiculite, so this step may not be necessary.
Shake the Bag to Remove Air Pockets and Fill the Edges
Your soil should be uniform throughout without any air pockets or bubbles. Giving the bag a good shake will help mitigate this problem.
If you have a large bag, add potting mix little by little, shaking the soil level as you go.
Leave a Few Inches of Space at the Top
Don't fill your bag all the way up to the top. Leave a little space to allow room to cover the soil with mulch. Not only will this improve your plant's appearance, but it will also help your grow bag retain water.
I also prefer to roll down the top edge of the bag to give it more stability. It also prevents the handles from sticking up, giving all the containers a more uniform appearance.
Don't Add Too Many Plants to One Bag
Remember to consider the spacing of each plant. The seed packet or plant label will indicate how far apart each plant should be.
Crowding can cause plants to compete for nutrients. Also, plants near the edge of the bag may struggle to develop a strong root system, as the air will stunt their growth.
Place in a Spot with Good Sunlight
Once you have everything planted, it's time to place your new friend in the sun. Check each plant's specific sunlight needs.
The great thing about garden bags - you can always move them throughout the day if they need more sun!
Add Drip Irrigation or Place in Watering Pan
Finally, add a drip irrigation system to your garden bags for hassle-free watering. Some people opt to place their grow bag in a pan of water. As you fill up the pan, the water wicks up into the soil. Using pans is a great way to keep your plants watered if you need to be away for several days.
Hopefully you’ve learned something useful today about gardening with grow bags. If you’ve never tried grow bags before, give it a shot. You might be surprised at how easy they are to use – and how much your plants love them!