Can I Grow a Garden in My Garage?

Why Even Grow a Garage Garden?

It turns out that garage gardens have real advantages over backyard gardens. It’s easier to control the bugs. You control the lighting, water and air circulation. A big storm won’t flood out your plants. And the local deer and rabbits won’t eat your crop. For all of these benefits, you have to invest in a growing environment and the electricity to run it.

So is it possible to grow a garden in the garage? Yes, you can grow a very successful garden in the garage! You can use raised beds, grow shelves, grow boxes and grow tents. You can do soil, aquaponic and hydroponic gardening. You can do organic and conventional gardening. Professionals and amateurs have tackled all the problems of light, air, water and growing media, so there are many indoor garage gardening solutions. The biggest challenge with garage gardening is controlling the temperature.

What Does Your Garage Garden Need?

When you garden indoors, you need to provide a space, a growing medium, light, water, nutrients, air circulation, and a proper temperature range for your plants.

A friend who wants to garden has very little land and a garage he doesn’t use. I have land for a garden, but it seemed like such an interesting idea, I thought I’d investigate. There are some challenges to overcome. Gardens need water, rain, air, and sun, not exactly garage staples. 
It’s no more than you need to provide in an outdoor garden, in theory. In practice, you need to simulate nature to provide many of your plants’ necessities. You’ll need to simulate sunshine, rain, and a garden bed.

For space, you can convert the entire garage, or set aside part of the garage for your garden. The garden can be as small as a plant on a shelf, and as large as grow beds and lights spanning the entire garage.  Remodeling the garage is not required. You can build or buy a gardening solution that simplifies getting your plants what they need. You can grow horizontally and vertically. You can use pre-made solutions including grow shelves, grow stands, grow tents, grow boxes, grow bags, hydroponic buckets, pod kits, vertical planters, and raised bed gardens.

For a growing medium you can use soil, hydroponics, aquaponics and pretty much any other type.

You can use electric lights to meet your plants’ light needs. These can be as small as a simple incandescent light bulb lamp, all the way to rows of high intensity LED lamps. You might use hotter lamps for warmth, too.

Supplying water can be as simple as a bucket of water from the house, but might be as complex as outfitting the garage with new plumbing.

The nutrition delivery method depends on your growing medium. You might add fertilizer to the soil by hand. You might use an automatic fertilization system. If you use an aquaponic system, you will need to feed the fish so that their filtered waste can feed the plants. If you use a hydroponic deep water culture method, your plants will sit in an oxygenated nutrient solution. If you use a hydroponic nutrient film technique, your plant roots will be fed from wicking material that gathers nutrients from a stream as it flows downhill.

Gardens have a complex set of air circulation needs. Plants need carbon dioxide, oxygen and air movement. Plants need carbon dioxide along with water and light for photosynthesis. Plant roots need oxygen. Airflow stimulates root strength. Enclosed growing environments such as “grow tents” require air intake and exhaust mechanisms. Each growing system accounts for these air circulation needs. Soil contains the oxygen for plant roots. Water techniques use flowing water and wicking to transport nutrients without drowning the roots.

Temperature range can be a bit trickier. To best control temperature you would insulate, heat and air condition your garage. That’s not practical in all cases, and that’s fine, so long as you account for your garage temperature in your gardening plans.

Why Even Grow a Garage Garden?

It turns out that garage gardens have real advantages over backyard gardens. It’s easier to control the bugs. You control the lighting, water and air circulation. A big storm won’t flood out your plants. And the local deer and rabbits won’t eat your crop. For all of these benefits, you have to invest in a growing environment and the electricity to run it.

What Does Your Garage Garden Need?

When you garden indoors, you need to provide a space, a growing medium, light, water, nutrients, air circulation, and a proper temperature range for your plants.

For a growing medium you can use soil, hydroponics, aquaponics and pretty much any other type.

You can use electric lights to meet your plants’ light needs. These can be as small as a simple incandescent light bulb lamp, all the way to rows of high intensity LED lamps. You might use hotter lamps for warmth, too.

Supplying water can be as simple as a bucket of water from the house, but might be as complex as outfitting the garage with new plumbing.

The nutrition delivery method depends on your growing medium. You might add fertilizer to the soil by hand. You might use an automatic fertilization system. If you use an aquaponic system, you will need to feed the fish so that their filtered waste can feed the plants. If you use a hydroponic deep water culture method, your plants will sit in an oxygenated nutrient solution. If you use a hydroponic nutrient film technique, your plant roots will be fed from wicking material that gathers nutrients from a stream as it flows downhill.

Gardens have a complex set of air circulation needs. Plants need carbon dioxide, oxygen and air movement. Plants need carbon dioxide along with water and light for photosynthesis. Plant roots need oxygen. Airflow stimulates root strength. Enclosed growing environments such as “grow tents” require air intake and exhaust mechanisms. Each growing system accounts for these air circulation needs. Soil contains the oxygen for plant roots. Water techniques use flowing water and wicking to transport nutrients without drowning the roots.

Temperature range can be a bit trickier. To best control temperature you would insulate, heat and air condition your garage. That’s not practical in all cases, and that’s fine, so long as you account for your garage temperature in your gardening plans.

Is Your Garage an Indoor or an Outdoor Garden?

If your garage is not insulated, and your outside temperatures go below 50 deg. F. or above 85 deg. F., then consider your garage’s temperature in your initial garden plans.

If it’s 30 deg. F., outside, an un-insulated garage is about 30 deg. F. inside. Your garage’s temperature will be much closer to the outside temperature than the temperature inside your home.

So you will treat your garage garden as if it were outside. You won’t plant hot weather plants in the fall, and you won’t expect cold-weather plants to handle 95 deg. F. days.

In order to do that correctly, you can consult the USDA Hardiness Zone map for your area. A zone tells you whether or not a plant will thrive in the temperatures your area gets. A plant designated for Zone 7 will not last a winter in Zone 5. This only works for cold weather, though. The zones don’t account for how plants thrive in hot weather. Unless you’re growing tropical varieties, most (not all!) plants wither above 85 deg. F.

One advantage of indoor gardening is that the outside temperature is irrelevant to what you grow. Depending on your climate and budget, you might be able to create a garage garden that acts like an “indoor garden.”

How Do You Cool Down a Hot Garage Garden, or Warm Up a Cold Garage Garden?

Is your garage too hot for lettuce? Too cold for eggplant? How do you keep the outside temperature from wilting your un-insulated garage garden?

Some of the following solutions might work for your garage garden.

You could insulate the entire garage to control its temperature range. You would then add air conditioning and heat so that you decrease garage heat in the summer and increase it in the winter. This is the most effective but also the biggest and most expensive approach to the problem. You’d need to add foam or batting insulation and drywall to get a maximum effect. This would include insulating the doors, ceiling, walls, and windows, and then putting carpet or a raised floor over the concrete floor. This is not a small job, but it is a good idea for some garage gardeners.

Alternatively, you could set aside a small space to insulate inside the garage, creating a sub-room within the garage. This is also a big job, but might be appropriate for some gardeners. Like insulating the entire garage, sub-room framing and insulation would take a budget, time, space, materials and tools.

Water is cooler than soil, so in hot weather you could use water instead of soil, and use cooler LED grow lights with an air-cooled light reflector.  Hydroponic gardening is now easy even for beginners, with hydroponic herb and veggie grow kits starting at very low prices.

In cool weather you could use soil, which hangs onto warmth better than water. Use a warmer incandescent grow light with a canopy light reflector to increase warmth.

For optimum garage temperature control with the smallest budget, you could install a pre-fabricated “grow tent” inside your insulated garage sub-room.  Learn more about grow tents below.

If it’s really hot and water gardening is not enough to cool the plants, you could throw the kitchen sink at the problem:

1. create a garage sub-room using foam board insulation
2. install a hydroponic grow tent kit inside the insulated sub-room
3. replace the grow tent reflective lining with a white non-reflective lining
4. install a portable air conditioner inside the insulated sub-room
5. use an LED grow light

Remember to include venting the A/C out a window in your plans. Regardless of the method you use to get temperatures lower, only grow heat-loving plants in hot weather. For vegetable gardening, grow plants like tomatoes, cucumbers, corn, beans, bell peppers, eggplant, and okra.

And if it’s really cold and soil gardening is not enough to warm the plants, throw the cold-weather kitchen sink at the problem:

1. create a garage sub-room using foam board insulation

2. install a soil grow tent kit inside the insulated sub-room
3. don’t alter the grow tent’s reflective lining, except possibly with something even more reflective
4. install a heater that’s safe for this setup (i.e., not necessarily a space heater, which could cause a fire) inside the insulation shell
5. use an incandescent grow light inside a reflective canopy

Grow cold-loving plants in your cooler garage, including lettuce, cauliflower, broccoli, carrots, beets and spinach.

Create a Garage Garden Using Grow Shelves

Now we need to replace the soil that you won’t find on your garage floor. Grow shelves are a wonderfully compact and efficient way to vertically grow a prolific garden inside your garage.

A grow shelf has a minimum of two shelves, one over the other, of course. The bottom shelf holds the plants, and the one above it holds the grow light. Grow shelves can be as small as this or grow to many shelves tall.

Space: Grow shelves make great use of unused space. Most shelves I’ve seen are about 2 to 4 ft. wide, but their magic is that they are vertical. They take up unused vertical space. So if you plant your garage garden across the breadth of your garage, the garden will take away space from other garage storage and projects.  But if you plant your garden vertically, you get to keep your garage and garden in it too.

Growing Medium: Most grow shelves on the market are designed for soil or hydroponic gardening. Grow shelves are usually sold as kits, with instructions explaining the growing medium requirements.

Light: Another space-saving grow shelf feature is that it uses the undersides of the shelves. The grow lights hang from the bottom of the next shelf up. This allows you to stack your garden beds without any of them being in the shade. Each grow bed gets a lamp, without increasing the height of the overall shelf system. Lights are usually a cool LED but not all shelves will hold you to this if you want to change out your bulbs for warmth or color.

Water: Many grow shelves are designed to be self-watering. These models come with a watering pan and a wicking material (a material that pulls the water from the pan). You place the pan on the shelf. Put water in the pan. Place the wicking material in the water. Place the plant containers on top of the wicking material. The plants pull the water up from the soaked material. If the plants were sitting in the water their roots would starve for oxygen. The wicking material gives the plants both water and air at the same time.

Nutrition: You add grow shelf nutrition as you would a traditional garden fertilizer, depending on your plants’ needs.

Air Circulation: Unless you’re growing a stout lettuce or hardy microgreens, you will probably want a small fan aimed at your plants to stimulate stem growth. These don’t usually come with grow shelf kits so you would get this fan separately.

Temperature: Grow shelf plants are completely open to the air, so will be subject to the temperature of the garage.

Click here for the garage garden grow shelves we love.

Create a Garage Garden Using a Grow Box

A grow box (or “cabinet” or closet) is a garden environment inside a closed-door cabinet. Grow boxes are usually made of wood or another typical cabinet material. They include the cabinet, light, air circulation, and shelves.

Grow boxes have a plant bed area at the bottom and a grow light at the top. An exhaust fan and filter pull fresh air in and expel spent air. A reflective material lining the walls multiplies the grow light’s reach. Grow cabinets are often lockable. Use a grow cabinet to grow in soil or water. Grow boxes usually include an automatic light timer.

Very high-end grow boxes are completely automated. The light, water and nutrition are mechanically controlled so that the grow is almost completely hands-off.

The “grow tent” has all but replaced the grow box, with most grow box manufacturers offering both boxes and tents. Tents are much less expensive and much more portable than grow boxes.

So why would you get a grow box rather than a grow tent? Grow boxes tend to be lockable and opaque. They look like furniture rather than a garden environment. Growers concerned about prying eyes use grow boxes to hide their crops.

Create a Garage Garden in a Grow Tent

Grow tents allow you to create a controlled and prolific garden environment in a contained part of the garage. 

A “grow tent” is a lightweight portable room you can erect quite quickly in your garage. A grow tent helps the gardener control light, temperature, humidity and air circulation.

When you garden in the garage, you have to compensate for the lack of sun, rain, and soil. A  grow tent organizes and positions the lights, water, air circulation, and growing media for you in a fashion optimal for growing plants.

Grow tents have air and wire ports, light hanging poles and plant beds. They’re a gardening world inside a box inside your garage.

You need to get electricity and water to the tent, which can be as simple as bringing in an appropriately sized extension cord (the lower the “AWG” the heavier duty it is) and a garden hose.

A typical grow tent consists of poles that create a structural frame for a fabric exterior. Crossbars across the ceiling hold straps for the plant light and the tent exhaust fan and filter. The fabric is fashioned into portholes for the fan and electrical wires to exit. Usually there are stealth windows behind fabric covers so that you can look inside without opening the tent.

Use a Grow Tent to Control Light, Temperature and Pests

Grow tent walls are not going to be much help insulating plants against sub-freezing outdoor temperatures. But if you go above and re-read the temperature section of this article, you’ll that that you might be able to thwart temperature extremes using a grow tent inside an insulated sub-room of your garage. Many people use grow tents for indoor gardening, where the household insulation, heating and cooling create comfortable temperatures.

First, grow tents help you bridge the gap between a comfortable temperature and optimal germination and growing temperatures. An advanced gardener creates an optimal growing environment. The garage gardener has a better chance of success controlling the temperature, and a better chance of controlling the temperature using a grow tent.

Grow tents usually have a reflective material lining the tent interior. This material is designed to reflect more light onto the plants. It also creates more heat in the enclosed grow tent environment. This might be the heat you need in a cooler (but not too cool) garage.

On the other hand, if you want to avoid this heat buildup in a hot garage, lose the reflective liner and both the light and heat it creates. You could look for a white lined tent, but I think you’d have to cover the interior yourself because I didn’t see any white-lined tents in my search. Your mileage might vary.

Grow tent manufacturers line grow tents with reflective material because it increases cannabis yield. Whether this reflective phenomenon will increase the yield of your crop depend on the photon receptors in what you’re growing. Less expensive grow tents often have fabric pinhole and zipper light leaks that can decrease yield. So higher end tents are much more light proof.  If you are growing full-sun-loving plants, a grow tent will help you increase maximize your electric light source. To visualize this, imagine your plant on a grow shelf in the open garage; now visualize your plants inside a brightly lit box lined with a reflective surface. Grow tents provide a lot more photons to your sun-loving plants.

Grow tents seal off the garden from pests that would otherwise infest it. The tent creates an “indoor garden” inside your garage. This is a big advantage that tents have over grow shelves.

Should You Get a Bare Bones or a Complete Grow Tent Kit?

By itself, a grow tent is a pre-fab room waiting for equipment. It has portholes, windows, a door, zippers and ceiling bars to hang a light and fan. If you want to outfit a tent with your own light, exhaust fan, ducting and filter, and then separately purchase a hygrometer, light timer and fan controller, you could get this well-liked TopoLite grow tent frame and fabric cover.

But you could also get well thought-out grow tent kit that includes everything you need to start growing your garage garden.  Grow tent kits ensure that all of the components work together.

This TopoLite grow tent kit include a 2 x 2 x 4 ft. cloth tent, 300 watt LED grow light, carbon filter, exhaust fan, exhaust ducting, thermometer-hygrometer, mechanical timer, bonsai shears, plant trellis netting, light hanging straps and a fan speed controller. You shouldn’t need a small fan to stimulate stem growth as grow tent air circulation creates air movement. So this is a complete garage growing garden tent kit, including a free pair of scissors. It’s a sturdy kit, well thought-out and backed by a well-liked customer-oriented company.

How to Set Up a Grow Tent

How to Start Using a Grow Tent

GrowAce created this excellent video showing how to populate one of their grow tents with plants and nutrients. This video gives you a good idea of the steps. First, mix the growing media. They are using coco and perlite. Then put the media in the grow bag. They instruct you to buy plant clones, but that just means that existing plants are easier to grow than seeds.  Having said that, plant clones are a really popular way to create new plants from existing plants, as plants are capable of asexual reproduction.  You will place the plants in the grow bags and install the grow bags into your grow tent.

Next, they explain how to test if your water source will work for your plants. Dissolved solids can get in the way of a plant absorbing nutrients.  If there are dissolved solids in your water, you might need to set up a reverse osmosis system. Or you could buy distilled water by the gallon.

Next, you will calibrate the pH pen that comes with this particular grow tent system. The pH pen has a screw you adjust to modify the reading until it matches a control sample. The kit comes with two packets that treat the water so that one has a pH of 4 and the other a pH of 6. You will calibrate the pen until it reads correctly against these targets. Then you will adjust the nutrition pH until it meets the pH in the fertilizer directions.

Each of these summaries is part 1 of a multi-part series. Use the summaries and videos to get an idea of the steps you’ll take to use a grow tent in your garage.

The original video is on the last slide of this summary, or view it on YouTube here.