Can You Use Grow Bags Indoors? (Just Don’t Ruin Your Floors)

Grow bags are a great way to create portable plantings outdoors.  However, many gardeners wonder if they can use grow bags indoors, and if so, how they should go about it.

So, can you use grow bags indoors?  You can use grow bags indoors, as long as you take care in choosing a location.  You will need to choose a place with enough light, make sure there are drainage holes in the grow bag, and put a container underneath to catch excess water.  You will also need to use the right type of soil for your plants and find a way to water them.

Once you take care of these steps, you will be well on your way to growing indoors!

Of course, if you’re at a loss as to what you might plant in a grow bag, don’t worry. I have some ideas for you.

In this article, we’ll talk about using grow bags indoors and what to think about before you do. We’ll also discuss what to plant in them.

Let’s get started.

Can You Use Grow Bags Indoors?

You can use grow bags indoors, but there are several considerations before you get started:

• Choose the right size grow bag – microgreens will not grow as tall (or need as much soil depth) as fully grown tomato plants. Size varies from tiny grow bags all the way up to huge ones that can hold 200 gallons or more!
• Find a good location – the ideal location for a grow bag will have plenty of sunlight. It will also avoid cold drafts of air from leaky windows and hot air from ventilation ducts.
• Use the best soil – sandy soil drains fast, while clay soil retains water. The best soil to use will depend on what plant you are growing. You can also find soilless potting mix or seed starting mix for microgreens.
• Setup your watering – whether you use a spray bottle (for microgreens) or an automated electronic watering system, figure out how you want to water your plants.
• Ensure adequate drainage – water may eventually pass through soil and the grow bag itself. However, drainage holes will help to speed up the process, just in case you ever over water your plants.
• Catch excess water – use a plastic tray or waterproof container under the grow bag to catch water that passes through. This will save your floors from getting ruined!
• Support your plants – taller plants may need support so they don’t fall over and start growing across your floor. This is not really necessary for microgreens, but tomatoes may need support at some point. Stakes or tomato cages work well for this purpose.

What Size Grow Bag For Vegetables?

Grow bags come in sizes from 1 gallon to to over 200 gallons!  The size you need will depend on the plant you want to grow.

Generally, you won’t be able to grow large plants indoors, due to space constraints (and the fact that your ceiling height will only accommodate shorter plants.)

Check out the table below to find out which size grow bag you should use by plant type.

Note: the bag should be deep enough to accommodate roots (for carrots, this is most of the plant!)

For more information, check out this article from Thrifty Fun on container sizes for vegetables.

Of course, you can use larger containers and grow a few plants in each container. Just make sure to give them enough space to avoid overcrowding and competition between plants!

Choosing A Location For Your Indoor Grow Bag

Before you fill up your grow bag with soil, you will want to put it in the right location. That way, you won’t have to move a heavy bag of soil too far.

Find a location near a window or skylight that will get plenty of sunlight during the day. This is especially important if you are growing in the winter when the days are shorter.

A south-facing window is your best bet, especially for plants that need full sun (such as tomatoes.) If you can’t find a spot with enough sunlight, consider using grow lights – just don’t leave them on all the time.

Also, be sure to avoid locations that have draft. Your plants won’t like shocks of hot or cold air from HVAC systems.

Finally, remember that dark colored grow bags absorb more energy from sunlight and get warmer during the day.  If you keep your house cool, a darker grow bag will help your plants to stay a few extra degrees warmer.

Should You Put Drainage Holes In Grow Bags?

You should put drainage holes in your grow bags for plants that do not like wet soil.  Even though the grow bag material may allow water to seep out, it will happen faster with drainage holes.

Some grow bags already have drainage holes in the sides or bottom.  If not, you can use scissors or a knife to create drainage holes yourself.

Make sure to do this before you put soil in the grow bag – it will make your life much easier!

What Do You Put Under Grow Bags?

As you can guess, any excess water that drains out of the bottom or sides of a grow bag needs to be caught. Otherwise, it will end up all over your floor.

You can put a grow bag on a saucer of the appropriate size, similar to what you would use for a plastic or clay pot.

You can also set your grow bag right inside a metal catering tray.  These trays are meant to hold liquid and remain sturdy. They can be reused many times over the years without breaking down.

If you have multiple grow bags, you can put them all inside a plastic bin, which can catch and hold the water from all of your grow bags.

Remember that you don’t want to leave too much water sitting inside these containers.  Either use a cup to recycle the water for your plants after the soil dries out a bit, or transport the water outside using a bucket.

Adding Soil To Your Indoor Grow Bag

The soil you use in your grow bag will depend on what you are trying to grow.  Many plant varieties will do fine with a potting soil mix from a local garden center.

On the other hand, carrots prefer loose, sandy soil.  They will fork and grow deformed when they run into rocks or soil clumps.

Your best bet for carrots is to sift rocks out of your soil, break up any soil clumps, and add some sand to make the mixture smoother.

When putting soil in your grow bag, don’t fill it all the way to the top. Otherwise, you won’t have a place to put your plant, and water or soil will spill out when you water the plant.

Instead, put some soil in the grow bag, leaving enough space for your plant and its roots.  Then, put your plant in the grow bag, and cover the roots with some more soil.

Leave the soil level a few inches below the top of the grow bag.  If the soil settles down later, you can always add a little more to the bag.

Plants To Grow Indoors Using Grow Bags

To grow plants indoors, you will want to choose shallow rooted plants that will not grow too tall or wide.  This means growing miniature varieties of tomatoes, lettuce, and other common crops.

Microgreens

Microgreens are simply the seedlings of plants that are harvested before they grow to maturity.  Microgreens are packed with vitamins and minerals.

Microgreens have a variety of interesting flavors that you can enjoy. For example, you can use the following seeds to grow microgreens:

• Arugula
• Beets
• Broccoli
• Mustard
• Peas
• Radishes
• Sunflowers

For microgreens, the grow bag does not need to be very deep. You will get more microgreens from a wider but shallower bag.

Lettuce

Lettuce is a fast-growing plant, and there are some compact varieties that would do well in smaller grow bags indoors.

Here are a couple small lettuce varieties you can try:

• Breen Lettuce – this is a miniature romaine type lettuce that produces small heads with bronze-red leaves. This variety matures in 45 days, giving you lettuce in 6 or 7 weeks after planting. For more information, check out Breen organic lettuce from Johnny’s Selected Seeds.
• Little Gem Lettuce – this is a miniature green Romaine lettuce that produces tender leaves.  The heads are about 4 inches across.  At 30 to 50 days to maturity, you can have heads of lettuce a month or two after planting!  These seeds germinate in 7 to 10 days.  For more information, check out Little Gem Lettuce on the Urban Farmer Seeds website.
• Newham Lettuce – this is a little gem type lettuce that produces compact heads that are shaped like vases. This variety matures in 52 days, giving you fresh lettuce for salads in under 8 weeks. For more information, check out Newham Lettuce from Johnny’s Selected Seeds.
• Tom Thumb Butterhead Lettuce – this is a Bibb type lettuce that produces small, compact heads that are about the size of a tennis ball.  One head will make salad for two people!  This variety matures in 50 to 70 days, so if you have 7 to 10 small pots (sow a seed every 7 to 10 days), you will soon have a head of lettuce for salad every week!  These seeds germinate in 7 to 10 days.  For more information, check out Tom Thumb Butterhead Lettuce on the Urban Farmer Seeds website.

Tomatoes

Tomatoes are one of the most popular plants to grow in vegetable gardens.  Somehow, it would not feel right to exclude them from a list of plants for indoor grow bags.

Here are some smaller tomato varieties for an indoor grow bag:

• Andrina Tomato – this micro dwarf tomato variety works well in college dorm rooms, since it only grows 8 to 10 inches tall at maturity. However, don’t let the small size fool you – it can still produce a good crop of small tomatoes. The fruit matures 75 days after transplant, so it takes about 11 weeks to get ripe fruit. For more information, check out the Andrina Tomato on Renaissance Seeds.
• Sweet ‘n’ Neat Cherry Tomato – this compact tomato variety is perfect for balconies or window sills in dorm rooms.  The fruits are small (0.75 to 1 ounce) and grow in clusters like grapes.  The fruit matures in 48 days, so you can have tomatoes 7 weeks after transplanting!  The plant is a compact determinate, only growing 10 inches tall and 8 inches wide.  For more information, check out the Sweet ‘n’ Neat Cherry Tomato on the Bonnie Plants website.
• Tiny Tim Cherry Tomato – this tiny tomato variety is also great for the limited space in dorm rooms.  The fruits are small (1 inch in diameter), but you will get plenty of them from a single plant!  The plants are determinate, only growing to a height of 8 to 16 inches and a width of 6.5 inches.  The fruit matures in 60 days, meaning that you can have tomatoes about 9 weeks after transplanting.  For more information, check out the Tiny Tim Cherry Tomato on the West Coast Seeds website.
• Vilma Tomato – this dwarf tomato variety fits into small spaces, since the plant only grows to 8 inches tall. The nickel-sized fruit is deep-red when mature, and they grow in clusters of about 6. The fruit matures 65 days after transplant, giving you ripe fruit in about 9 weeks. For more information, check out the Vilma Tomato on Renaissance Seeds.

Remember that determinate tomato plants will produce fruit once and then die off. You can ensure a supply of fruit throughout the season if you stagger plantings every 1 or 2 weeks.

If you to grow taller tomato plants in a grow bag indoors, remember to provide support. A stake or cage will give them a place to climb and save space (via vertical gardening).

Basil

Basil is great because you can simply pick off a leaf here or there as needed, and the plant will continue to grow.  Together with tomatoes and lettuce, you can make a nice salad just from your indoor grow bag garden!

Here are some basil varieties you can grow in your indoor grow bags:

• Cinnamon Basil – this variety is smaller than sweet basil, with a darker color and a spicy cinnamon flavor.  This plant will grow 18 to 30 inches tall and 12 to 18 inches wide.  For more information, check out Cinnamon Basil on the Bonnie Plants website.
• Greek Dwarf Basil – this tiny basil variety has a flavor that is a mix of spicy and anise. The plant only grows 6 to 10 inches tall at maturity. For more information, check out Greek Dwarf Basil from Baker Creek Heirloom Seeds.
• Thai Basil – this variety has a stronger flavor than sweet basil, with a hint of licorice.  The leaves are also smaller than those of sweet basil, and they have purple stems, giving them a nice decorative appearance in dishes.  This plant will grow 1 to 2 feet tall and 1 to 2 feet wide.  For more information, check out Thai Basil on the Bonnie Plants website.
• Windowbox Mini Basil – this small basil variety has a rich aroma and is perfect for growing in a window box if you have one. The plants only reach a height of 8 to 10 inches. For more information, check out Windowbox Mini Basil from Renee’s Garden.

Other Plants For Indoor Grow Bags

You can also grow the following crops using indoor grow bags:

• carrots
• radishes
• onions

These plants will not get too large and the roots will not grow too deep. Of course, my list is not exhaustive – there are lot of other plants you can grow in a grow bag, including flowers and houseplants.

See the table at the beginning of this article for more information on which size grow bag to choose for these plants.

How To Water Plants In A Grow Bag Indoors

You can certainly water your indoor grow bag manually, especially if you have a saucer or container underneath to catch any excess water.  However, you can also try the water bottle method to water your grow bag plants automatically.

To do this, take a plastic water bottle and poke holes in the bottom (put more holes for faster water release).  Then, put the water bottle into the soil, with the bottom of the bottle down (so the holes are under the soil).

Finally, fill the bottle with water.  It will slowly drain out into the soil, keeping the plant watered if you are away on vacation or have too many plants to water manually.

Simply refill the bottle every so often to keep the plant supplied with water.

How To Support Plants In A Grow Bag Indoors

Some plants (such as tomatoes) always like to have some support as they grow.  A small tomato cage can help tomato plants to stay upright instead of crawling up and over the edges of the grow bag.

For more information, check out my article on tomato cages.

Conclusion

Now you know that you can use grow bags indoors.  You also have an idea of how to get started and what you will need to consider when deciding on the details of using in grow bags indoors.

For more information, check out my article on how long grow bags last, and my article on the pros and cons of grow bags.

You might also want to check out my article on the best vegetables to grow indoors.

I hope you found this article helpful – if so, please share it with someone who can use the information.

If a lack of space is holding you back from gardening, check out my article on how to start a garden without a yard.

If you want to read some of my most popular posts, check out the “Best of GreenUpSide” page here.  Enjoy!

~Jonathon