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Vegetable seed and gardening supply sales have skyrocketed in the past month. Producers are reporting that most of these sales are new customers in urban areas (source). As more people in densely-populated areas turn towards growing their own food, they will end up facing unique obstacles.
Apartment dwellers make up at least 50% of urban residents (source), meaning quite a few of these aspiring green thumbs have little to no outdoor space and limited use of their indoor space.
Besides the obvious challenge of finding a spot to plant seeds, these growers will have to battle limited light, low air circulation, pests, containing water drainage, and producing enough in a small space to make a difference in their grocery budget.
If you have a small balcony, it’s easy to grow a few vegetables in containers or a small raised bed. However, if you don’t have a balcony or outdoor living space, growing vegetables is much more difficult.
It is possible to grow a substantial amount of vegetables in an apartment without a balcony if you have the right equipment. The key is identifying what will produce the most value per square foot, and designing a system that costs less than buying your harvest at the grocery store.
First, decide how much space you can devote to an indoor garden, both horizontal and vertical space. The closer to a window, the better the lighting situation, but you can also grow successfully in basements or garages with supplemental lighting. Next, make a list of what you want to grow, and begin planning your system.
Basic Indoor Garden Setup
While the type of system you choose will vary depending on which plants you want to grow, how many you want to plant, and how often you want to harvest, all systems will have to supply for the basic needs of plant growth.
Any plant you grow indoors will need 4 basic inputs to produce a healthy, substantial harvest:
There is not enough natural light indoors to grow vegetables. No matter what vegetable you wish to grow, even a well-lit windowsill is not sufficient for growing vegetables.
The only exception may be one small container of herbs, or a trellis in a window for peas. Even then, these plants would be much healthier with supplemental light.
Any indoor garden system will need supplemental lighting. LED lights are ideal because they can direct all of their output in one focused direction.
They are also extremely efficient and produce no heat. Fluorescent lightbulbs are a good second option, although you will need an additional fixture to direct the light down onto the leaves.
Most indoor gardens will not use soil. Soil is heavy, messy, and can easily breed pests in an indoor environment.
Instead, indoor systems generally use rockwool, coconut coir, clay pebbles, or a soilless mix using perlite or vermiculite. There are many different options for growing media, and the best place to find them is hydroponic suppliers.
However, these growin media all have one thing in common: they are sterile. This means they have no nutrient value, which means you must invest in a fertilizer.
Water is crucial for plant growth. While outdoor garden systems focus on planting in soil and adding water, many indoor systems focus on planting in water with a minimal amount of growing media.
However you decide to design your growing system, you need to have a plan for watering your plants and containing drainage. Outdoors, water can leach down into the soil or evaporate from the surface. Indoors, water does not evaporate easily. Freely-draining soil media is crucial for indoor plant root health.
Indoor garden systems need to be able to hold moist growing media, give roots room to grow out and down, drain and collect excess moisture, and not rot or mold in this environment.
The best material for a small growing system is some sort of plastic bin or tote setup. Bins can be supported by a wooden frame as long as the wood is treated in some way to prevent water damage.
For larger systems, metal containers may be easier. They can support more weight than plastic, and they come in larger sizes than most totes. However, they can rust and may have sharp edges. You will need to do a substantial amount of work to get them to drain properly.
For a custom system, IBC totes are the best bet. They are easy to find, and combine the best aspects of plastic and metal. The containers themselves are plastic, making them lightweight and easy to shape. But, they come with a built-in metal frame, making them easy to support.
What Vegetables Grow Well In An Apartment?
With enough space, light, and water, and heat, you can grow any vegetable indoors. However, many large vegetables are not worth the amount of time and space required for a decent harvest.
The main consideration for growing indoors is whether or not you need the plant to flower. Tomatoes, peppers, cucumbers, beans, peas, and other flowering vegetables will take more time, space, heat, and specific lighting conditions to have a decent harvest. Lettuce, carrots, onions, radishes, herbs, and other non-flowering vegetables are less picky about their growing conditions and take up much less space.
Leafy greens are easy to grow indoors because it’s easy to keep them from flowering. These plants need a spike in warm weather and direct sunlight to promote flowering, and this is an extremely difficult environment to reproduce indoors. Therefore, it is easy to grow leafy greens and keep them in production without flowering for extended periods of time.
This is perhaps the easiest vegetable to grow indoors. Lettuce can tolerate less light than most other vegetables, and you can find a shade-tolerant variety that handles indoor growing easily. It is part of the Aster family, which means it’s related to daisies.
The downside to lettuce is that it’s also extremely cheap at the grocery store. It may not be worth dedicating a portion of your apartment to growing lettuce when it is so easy to purchase.
These leafy greens are all in the Brassica family, along with broccoli, cabbage, and cauliflower. These leafy greens are much more nutritious than lettuce, which means they require more nutrient-dense growing media.
These veggies grow best in cooler temperatures, so they handle indoor growing well as long as there is sufficient light. However, they are prone to pests so adequate airflow is a must.
Spinach is yet another leafy green, but in the Amaranth family. This is a family that is known for flowers, so it’s important to keep spinach from flowering in order to be able to harvest the leaves.
There are many different varieties of spinach, so it is easy to find one that is suitable for indoor use.
While root vegetables can be easier than flowering vegetables to grow indoors, they can be a bit of a challenge. Root vegetables need depth and flexibility in their growing media in order to expand and mature.
The good news is that root vegetables like cooler temperatures, so they do well with indoor growing. However, they will need a deeper growing area to accommodate their growth.
These veggies are Brassicas, so they are similar to kale, chard, and broccoli. Radishes like cool temperatures, full sun, and well-draining growing media.
The benefit to growing these root crops is that they mature quickly and hold well. There are many different varieties of radish and turnip, and while some are easy to find in grocery stores, there are gourmet varieties that are more difficult to find that are easy to grow indoors.
Carrots are related to parsley, and both are easy to grow and maintain. Carrots need well-drained, loose growing media that is at least 6” deep.
As long as carrots have direct light and air movement, they can grow well indoors. Mix them in with other vegetables if you have a soil-based grow bed.
Onions are technically a stem, and garlic is a bulb, but both belong to the Allium family and have similar growth requirements as other root vegetables. These plants are generally pest-free as long as they have well-drained growing media.
While onions and garlic are easy to find in grocery stores, these strong-smelling plants will help detract pests from other vegetables, which makes them multi-functional. Plant them with other vegetables in a soil-based grow bed to help ward off pests.
Herbs are the easiest plant to grow indoors. They’re also a high-value crop, which makes it well worth the effort to set up a growing space.
The downside to growing herbs is that they aren’t food; they’re seasonings. However, with a little investment, you can set up a growing space that lets you grow a wide variety of herbs that allows you to make your own seasonings and herbal teas.
Growing Fruits & Fruiting Vegetables Indoors
Fruits and fruiting vegetables are difficult to grow indoors. They need more space, light, and heat than leafy greens or root crops. They also have a limited time when you can harvest from them.
The biggest challenge to indoor fruits and fruiting vegetables is pollination. Some plants are wind pollinated, which you can simulate with fans or by shaking the plants to release pollen. Other plants, like cucumbers and melons, require manual pollination, which you can simulate with a paintbrush.
However, there are many types of fruiting crops that you can’t find in stores, which makes them fun to grow yourself as long as you have a plan for how to use them.
Tomatoes can become enormous miniature trees in the right conditions, so they can be difficult to grow indoors. However, there are well over 10,000 varieties of tomato, so you can grow some unique and delicious fruit if you can create the right space.
Tomatoes need heat, light, water, and support in order to produce a large amount of fruit. Determinate varieties will grow into more of a bush, while indeterminate varieties are vines that can be trained up a support structure.
Peppers have similar growing requirements to tomatoes, but they don’t grow as tall. There are over 50,000 varieties of peppers, which means you can grow quite a collection with the right equipment.
Spicy peppers will need more heat and light than sweet peppers (although neither can tolerate shade or cool temperatures). They are easier to contain than tomatoes, and many peppers can be dried for later use.
Cucumbers are difficult to grow indoors because they have male and female flowers. This means in order to produce fruit, pollen has to travel from a male flower to a female flower. Outdoors, this is accomplished with insects. Indoors, it can be tricky.
When a cucumber vine begins flowering, you can use a paintbrush to transfer pollen between flowers and encourage fruit set. However, this is time consuming and may not be worth the effort unless you are growing a unique variety of cucumber.
The benefit to cucumbers is that the fruit is light, so you can easily train the vines up a trellis to save space.
Watermelons, cantaloupe, pumpkins, butternut squash, and many other vining fruits fit into this category. Their growth requirements are similar to cucumbers, but they require far more space and are hard to contain.
The downside to these fruits is that they’re heavy, which means trellising them is very difficult and sometimes impossible depending on the variety. However, there are many unique varieties that are impossible to find in grocery stores, so if you have the space and the ability to produce enough light, it may be worth the investment.
These fruiting veggies are both legumes, which means they have little nutrient requirements compared to other fruiting plants. You can either grow a vining variety to help conserve space, or a bush variety to grow them in containers.
Fans or gently shaking the plants will stimulate pollination, and with the right growing conditions, these veggies will produce for quite a while. There are unique, purple podded varieties and other heirloom varieties that can make growing these plants indoors worth the effort.
Blackberries, raspberries, and blueberries all grow on large shrubs, making them difficult for indoor production. Grapes are long, twining vines, making them equally as hard.
However, there are a few fruits that can be grown indoors, like strawberries, ground cherries, and gooseberries. These fruits are beyond the scope of this article, but if you want to grow fruits indoors, strawberries are the best place to start.
This is a large category, and largely impossible in an apartment setting. However, there are a few varieties of container fruit trees that can handle lower humidity and temperatures than an outdoor growing space.
The difficulty with most fruit is that these trees require a dormant season (except citrus) in order to blossom each spring. This is difficult to induce indoors, which is why indoor fruit trees are nearly impossible. Plus, most fruit trees need insects for pollination.
Planning An Indoor Vegetable Garden
Once you have a general idea of how much space you can devote to an indoor garden, take some time to plan which plants you want to grow, and why you are growing them.
Consider which plants are either more difficult to find at a grocery store, or cost more than other items in the produce section. Indoor gardening also opens the option for growing rare and gourmet varieties of otherwise boring vegetables, so make a list of exactly which veggies and which varieties you are interested in growing.
Next, take your list of garden candidates and calculate how much of a harvest you can expect from each one. For example, one cherry tomato plant may yield 10lbs of fruit, while one head of lettuce is barely half a pound.
However, tomatoes generally all ripen in a 3-4 week period, while a cut-and-come-again lettuce variety may give you fresh salad leaves for months on end. Plus, a tomato plant will take up a 3’x3’ space, while that same space could house 9 heads of lettuce.
Research the plants you want to grow, how much space they need, how often they can be harvested, and their temperature requirements. Then, decide whether or not you will be able to use what you harvest at the time the vegetables are ready to be harvested.
Some plants may give a large, valuable harvest, but require more effort than the harvest is worth. For example, some varieties of squash are incredibly rare, making them costly and difficult to find. Growing your own is possible, and you would certainly gain a large volume, high value product. But, the amount of time and money it would take to grow squash successfully indoors is enormous. It’s simply not worth it.
Once you have narrowed your list of potential indoor vegetables down to a manageable size of reasonable value, decide how much you are willing to put in to a growing system. Include both time and money as inputs, as well as the energy cost of upkeep.
One of the best parts of indoor gardening is that it is summer whenever you want it to be summer. Your grow lights will put out enough light to grow most vegetables, and (hopefully) you never have a late freeze in your living room.
This means you can grow vegetables year round, giving you the ability to rotate and exchange crops throughout the year. You may grow warmer-weather plants in the winter time, when they are more difficult to grow outside or find in the store, and cooler-weather plants in the summer time. Or, you can rotate based on a canning schedule. Or individual taste. With rotation, the possibilities are endless. Just make sure you have a plan for how you will utilize your garden throughout the year, and take into account how long each plant need from germination to harvest.
Light Calculation For Indoor Vegetable Gardens
Once you have decided on your plant list, you will need to decide how to orient your grow lights and which kind of lights to buy. This is more difficult than it sounds, but in general, there is no such thing as too much light.
If you plan on growing mostly leafy crops or root crops, you can get away with fluorescent lights on an adjustable chain. The biggest concern with fluorescent lighting is wattage per square foot.
For leafy greens, you want to aim for 40-50 watts per square foot of growing space. This means for a 5’x5’ area, you will need 1,000-1,250 watts of output. However, most fluorescent bulbs only truly put out 1/3 of their stated wattage. For a 60w bulb, you can expect 20w to be available for plants.
Therefore, for a 5’x5’ area, you want to aim more for 3,000-3,750 watts per the label. The more light you can direct down to the growing area, the less wattage you need. This is a large amount of light for a small area, and it’s difficult to find these lightbulbs in hardware stores. Traditional fluorescent lightbulbs can work if they are changed regularly, and as long as the plants remain green and bushy, they are getting enough light. Use cool lightbulbs (above 3000k) for leafy greens and root crops.
LEDs are the best grow lights. While fluorescent bulbs put out about 1/3 of the advertised output, LEDs are more efficient and can focus their output in one direction.
For flowering plants, LEDs are essential. Plants need blue light for leaf growth and red light to induce flowering. With LED fixtures, you can set them on blue while the plants are young, and switch over to red as they mature and begin to flower. This is difficult with fluorescent lightbulbs because they are either red (under 3000k) or blue (over 3000k) and changing the light color means changing out the bulbs.
Flowering plants need more wattage per square foot, so aim for 60 watts per square foot of growing space. Lights should be no more than 6” above the top of the plant to maximize light use.
While lighting for indoor gardening can be a complex calculation, it’s also not exact. A system in a basement with no windows will need the full wattage per square foot from supplemental lighting. A system next to a well-lit window can thrive with less supplemental lighting due to natural sunlight. Overall, if plants look bushy and deep green, they have enough light. If they are long, leggy, and reaching, move the lights closer to the plants and add more lightbulbs.
Three Common Indoor Vegetable Garden Systems
Now that you’ve decided which plants you want to grow, and how many, it’s time to design a system. We will cover the three basic setups, but you can customize them to fit your space and growing goals.
No matter which system you choose to build, there are some components that have to be implemented in all of them:
Air movement – Make sure you have fans to circulate air around your plants.
Fertilizer – Most indoor systems use a soilless, sterile media. Find a water-soluble fertilizer to provide nutrients.
Consistent lighting – Plants need a dark period each night to utilize the energy they create during the day. This needs to be consistent. When day length changes, plants think the seasons are changing, and they may stop growing or begin bolting. Consider timers for consistent light times.
This is the simplest indoor growing method. You can use almost anything for a plant container, including old juice bottles, milk jugs, plastic totes, glass jars, and buckets. You can use soil for this method, or you can use a soilless growing media. Look for growing medias from raised bed garden suppliers.
Use larger containers for plants with complex root systems, and smaller containers for plants with shallow root systems. In general, the larger the plant, the larger the container. Make sure all containers have adequate drainage.
The difficulty with containers is catching the water that leaches through after watering. Obviously, you don’t want this water draining onto your floor. Most recycled plant containers don’t come with drip pans like terra cotta pots.
If you place containers on shelves, you can let the water from one shelf drip down onto the plants below. However, this can cause mold problems, and you will still need to catch runoff at some point.
The easiest way to do this is to put your containers on stands. They don’t need to be tall; just enough to allow the water to drain. Put your containers on a table or shelf with a non-porous surface, and build a small lip around the edge to prevent dripping. You can either create a slight tilt to drain water into one location, or mop up the water with a towel.
You can also fashion makeshift drain pans for your containers and empty them each day. These give you more flexibility, but leaving the water will create pest problems, so make sure you empty them consistently.
Containers can be placed on shelves for vertical gardening spaces, or on tables to accommodate taller plants. It is difficult to support trailing plants in containers, so this system is best for leafy greens, root crops, herbs, tomatoes, and peppers.
Vertical window gardens
These systems are great because they maximize natural sunlight and minimize how much space you need to dedicate to your plants. However, they are tall and skinny, so it rules out large, bushy plants like tomatoes and peppers.
You can use PVC pipe and build a zig-zag structure like those marble toys, and drill holes in the top where you want to plant each plant. Then, as you water, the excess will travel down through the pipe and empty into a bucket at the bottom. This system works great for small, leafy greens, herbs, and strawberries.
You can also use a long, skinny container that fits in the windowsill and string twine up to the top of the windowsill to create a trellis. This setup works well for beans, peas, cucumbers, and a few miniature varieties of melons and squash. You will need to put this container on a small stand with drain pans underneath. Once the plants latch on to the twine, you can’t pick up the container each day to drain the excess water from a drip pan. So, you need a permanent stand with movable pans.
You will still need supplemental lighting in this setup, but you can also harness the natural light by building a reflective wall to bounce sunlight back towards your plants. This greatly reduces the need for supplemental light, and may even support leafy greens and herbs by itself.
If you want to grow large amounts of vegetables and fruits indoors, you need some sort of water-based growing system. The easiest system to build is a hydroponic system. If you want to have a source of protein on occasion, you can build an aquaponic system, which uses fish as the main source of nutrients.
A basic hydroponic system has a grow bed and a holding tank. Every 45 minutes, the holding tank pumps water through the grow bed and saturates the roots with nutrient-rich water. It holds water for 15 minutes, then drains back into the holding tank. Aerators keep the water full of dissolved oxygen.
You can use floating styrofoam mats in the grow bed to suspend plants in the water, or you can fill the grow bed with clay pebbles and plant them like you would in soil. You can also use PVC, drill holes in the top for plants, and pump water through a maze of piping.
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Aquaponics is basically the same, but the holding tank needs to be able to support fish. The benefit of these systems is that you can grow much more per square foot than any other growing system (including traditional raised beds). You can also grow plants to maturity faster, meaning you can harvest more plants, more often, which means you can grow more of your food at home.
The downside to this system is that it’s full of water. If the pumps stop working, your plants die. If there’s a leak, you’re looking at massive water damage. Water means algae blooms, so you have to become a layman chemist in order to maintain the nutrient levels properly.
However, these systems are easy to add on to and you can grow almost anything in them, except woody herbs. You can also put these systems in basements or garages, if you have enough supplemental light, and grow a substantial amount of food.
You can build a simple aquaponics system to grow your own organic food. Click here to learn more.
Consistent airflow is extremely important in water-based growing systems, so make sure you have fans running constantly.
Building a hydroponic system is beyond the scope of this article, but there are many DIY kits available, and with a little construction knowledge, you can customize your own system for fairly cheap. The best materials for these systems are recycled 55-gallon drums, IBC totes, and plastic bins.
Growing your own food is a fun adventure, and it opens up the possibility of growing new and unique vegetable varieties. As you begin growing indoors, you can work towards building a self-sufficiency garden that provides fresh, healthy vegetables year-round.