Skip to main content

How small is too small for an indoor greenhouse?

When people think of greenhouses, huge buildings with hundreds of plants inside comes to mind. However, in actuality, greenhouses come in all shapes and sizes. It may seem almost impossible to create a greenhouse for a tight space, such as an apartment or home with no backyard, but greenhouses can range in size from a 1×1-foot box to a huge 26×12-foot monster. It all depends on your space and what you want to grow.

Anyone can create a DIY indoor greenhouse with proper planning and foresight. Do not let having a small space deter you from growing your own fruits and veggies right inside your home. There are greenhouses in every size, even ones that fit right on a windowsill. Let us break down what size is best for an inside space.

A person in a blue shirt holding a brown basket full of assorted vegetables, including carrots, tomatoes, potatoes, onions, and lettuce
Tatevosian Yana/Shutterstock

Best plants to grow inside

The first decision to make is what plants you want to grow inside your greenhouse. Some fruits and veggies take up more space than others and will determine the space needed. For herbs, we recommend hardier options, such as thyme, rosemary, and sage. Basil, parsley, and cilantro will also grow well indoors. Veggies are a little trickier because they can take up a decent amount of space, but our recommendations include hot peppers, tomatoes, spinach, and radishes. Fruits are some of the easiest options because most are small and grow quickly indoors for a healthy snack all year long; we recommend grapes, strawberries, and gooseberries.

If you’re looking for flowers rather than edible options, there are a multitude of flowers that will thrive in an indoor greenhouse. If you have enough space, you can grow beautiful varieties, such as peace lilies, hostas, marigolds, and chrysanthemums.

Spacious Lounge With Indoor Greenhouse
Photo by Max Vakhtbovych/Pexels

Determining the size of your greenhouse

Now that you have chosen which plants you want to grow, you can move forward with selecting the size. This can depend on many factors, including the plants, but also the limits of your indoor space and the location of your greenhouse, e.g. close to a window for sunlight. If you’re simply growing a few herbs and maybe some stalks of cherry tomatoes, then you’re in luck because a simple 5×5-inch growing tray will be enough. However, if you are looking to grow bigger plants, such as small trees like avocados, then you will need to take their size into account.

Pro tip: Go vertical! Five-foot tall, vertical greenhouses work wonders for small spaces because you get the height needed without encroaching on the rest of your home. These are multi-tiered options that allow you to grow a lot of plants at once while saving space.

Environmental factors

Unlike a sprawling outdoor greenhouse, the indoor versions may need a little more help. There a number of things you should keep in mind when selecting the location of your indoor greenhouse.

Sunlight or grow lights

Obviously, sunlight is one of the most important parts about growing plants. Put your greenhouse somewhere that gets the most sunlight throughout the day. Natural light is best, but you can use grow lights to help if you live in a cloudy area or do not have a lot of windows. Just be aware that some grow lights can produce a lot of heat so set a timer before your plants wilt.

Temperature

In general, growing plants need to be in a space with a temperature between 65° to 75° F. Your home may fall in that range, but it is a wise investment to have an easy option control the temperature. For heat, a tea light or small electric heater can work wonders, while a small fan can lower the temperature fairly quickly. The nighttime temperatures should be 10 to 15 degrees cooler than the daytime temperatures so keep that in mind before you head to bed.

Humidity

The humidity of a home is a little harder to control, especially when summer hits. Even if your indoor plants are protected from the hot temperatures, they still can “feel’ how it is outside. Keep an eye on your plants’ leaves and stems; if either are turning brown, your plants probably need more moisture due to low humidity. Either get a humidifier for the space or mist the plants at least once a day.

Indoor greenhouses are not impossible to make and can work wonders for anyone living in a small space. If you’re looking to grow a few small herbs, your greenhouse can be as simple as growing trays inside of a box with a small heater. Choose the best space to get the plants proper sunlight, temperature, and humidity, and if you need a bigger greenhouse because you want to go all out, check out the vertical greenhouses. There are many options so you won’t have any excuses not to start growing your own indoor plants.

Editors' Recommendations

Niko Vercelletto
Former Digital Trends Contributor
Niko Vercelletto lives in Lansing, Michigan. He is passionate about going into depressive spirals thanks to the Detroit Lions…
A complete guide to cleaning your greenhouse for beginners
greenhouse

When you first installed your greenhouse, it probably looked like a glittery glass castle for your lovely plants to grow and live in. However, weather, soil spills, and birds have made their mark on your greenhouse over time and now it's probably looking cloudy and nasty. So how do you clean a greenhouse?
Why worry about a clean greenhouse?
You may be wondering if you even need to worry about cleaning your greenhouse. If you don't mind the dirty look, maybe you could leave it as it is? Unfortunately, it's much better for your greenhouse and your plants if you give the greenhouse a deep clean at least once a year. It'll make it easier to use when it is clean and organized, and the walls of the greenhouse need to be clear so they can let in as much light as possible. Additionally, a clean greenhouse is less likely to spread pests and diseases to your precious plants. And lastly, things last longer when you care for them and greenhouses aren't cheap.

When should you clean a greenhouse?
There's no right time to clean a greenhouse; whenever you can is better than not at all. However, we suggest cleaning it when there isn't so much to do in the garden and it isn't so hot out. Usually, the fall is when the garden chores slow down and it starts to cool out, making cleaning the greenhouse much easier on you.
What is the best way to clean a greenhouse?
You can use whatever cleaning method works for you, but here is our step-by-step process that we recommend.
Step one: Empty the space
Of course, we know you can only empty a greenhouse so much if you have tender plants that need to stay warm. But as much as you can, take out the tools, buckets, and bags of soil. It will be much easier on you if you don't have to fuss with items in your way as you clean the walls and floors. This also allows you to go through what you have and declutter if necessary.
Step two: Rough dusting
Over the season, spiders and bugs and maybe even some mice have tried to make homes in your greenhouse. This has probably led to a few cobwebs and dust piles around the corners. You'll want to remove these large areas of debris before you start the deep cleaning. Use a broom to knock down the cobwebs and sweep up the floor; you've probably spilled some soil during the summer!
Step three: Clean the walls
The panels of your greenhouse will now need to be deep cleaned. You can use a bucket of warm water and a sponge to wipe them down, but we also recommend bringing a long-handled brush to make life easier. This way, you can dip the brush into the bucket of soapy water and scrub down the walls with the long-handled brush. You'll be able to reach every inch of the walls without killing your back.

Read more
When and how to transplant tomato plants for the best results
baby tomato plants

There's a time in every gardener's life when they try to grow their own veggie plants from seed. This is a gratifying process, and there are many benefits to growing your own seed starts. One of those benefits is bigger and healthier plants. By growing your own baby tomato plants, you can ensure that the plants are well cared for, never given anything you don't want them to have, and transplanted in just the right way at just the right time for optimal plant health. So how do you transplant tomato plants to ensure they're happy and healthy and live to produce lots of yummy tomatoes for your home?

How do you transplant a grown tomato plant?
If you've never transplanted tomatoes before, the idea can be intimidating. You have all these tiny plants that you've cared for over the last several weeks, and now it's time to pluck them out of their nursery pots and plop them into the outside soil where they're exposed to sun, weather, and critters. Luckily, you've cared for them so well that they're healthy and robust plants that will be able to handle anything nature throws at them.
Step one: Harden the plants
Hardening the plants is a term gardeners use when talking about the process of acclimating a greenhouse-grown plant to outside conditions. Typically it refers to sunlight, but it could also refer to wind and other weather that could harm the plant. About a week before you're ready to transplant, you'll want to harden your baby tomato plants by exposing them to sunlight at increasing increments each day. For example, day one should be about 30 minutes, then 45, then 50, and so on until the day of transplanting. If you don't do this, you'll risk your plant being burnt and killed when you transplant it outside.
Step two: Don't water the plants
Before you start pulling little plants out of their pots, you mustn't water the plants a few days before transplanting. Wet soil can make the transplanting process much harder on you and the plant. Dry soil falls away easier and is less likely to break off roots as you move the plants to their new home.
Step three: Prepare the new soil
The new location for your tomato plants will need to be prepped before you get all those babies out of their homes. Whether you are planting into the ground, a raised bed, or a pot, you'll want to amend the soil to guarantee that the plant has many nutrients to soak up. It also is easier if you dampen the soil right before transplanting. Damp soil is much more manageable and more easily manipulated around the plant.
Step four: Plant deeply
As you gently pull out the baby tomato plants, you'll want to shake off the old soil to expose the roots. This will ensure the plant has access to the new soil and nutrients you're about to provide it with. 

Read more
A complete guide to the best lights to choose for your greenhouse
Houseplants under grow lights

Just like growing houseplants indoors, growing plants in a greenhouse requires specific care and a suitable environment. Even though the greenhouse will have some light from the sun coming in, the glass panes are often filtered in some kind of way to prevent your plant’s leaves from scorching. Enter grow lights. They’re used most commonly in darker spaces or during colder months; however, they're greatly beneficial to your greenhouse plants and help ensure that the plants are getting the light they need to thrive.

Can you have an indoor greenhouse?
Absolutely! Indoor greenhouses are revered for how sustainable and inexpensive they can be. An indoor greenhouse with lights can be installed anywhere in the home where you have the space, and it’s a perfect place to grow things like fruits, herbs, and veggies indoors. If you’re only planning to grow a couple herbs, you can get something as small as a tabletop greenhouse! It will fit a few plants, won’t take up too much space, and will add to the aesthetic of a room while letting you grow plants in a unique way.

Read more