How To Grow Vegetables Indoors – The Ultimate Guide

Growing your own groceries indoors year round, no matter how short the days are of the temperature outside, is a lot easier and less expensive than you may think.

Simply because you have a small yard or it is snowing outside does not mean you cannot grow fresh veggies and herbs for your family to consume.

There are probably far more crops you can grow indoors in the fall, winter, and spring than you ever imagined. You can rotate your vegetables and fruits outdoors during the summer months if you want, but do not have too.

For a long time I was too intimidated by all the “sciencey” stuff I would have to contend with to cultivate vegetables indoors to give it a go.

Having to regulate humidity, deal with poor natural light, adapting the plants to heat or air conditioning, and being solely responsible for how much water they would receive were only part of my concern about indoor growing in winter.

I was also worried about the cost. I poured over page after page of instructional guides that delved (in my opinion) far too deeply into the technical aspects involved with each lighting choice and other indoor gardening “must haves” in an effort to sell products.

It took a season of trial and error, but on a shoestring budget, armed with a decent amount of gardening smarts and a whole lot of common sense, I had a somewhat bountiful winter indoor growing harvest.

Since then, I have fine tuned my techniques, learned a lot, and perhaps most importantly, have simplified the process so other non-master gardeners like myself can grow a plethora of veggies and herbs indoors over the winter months, while waiting for the sun to come out and warm the ground again for spring planting.

We began to enjoy growing our crops indoors so much that we are now in the midst of turning a back room into an indoor greenhouse.

Even though we have 56 acres of potential growing space, the controlled climate of cultivating crops inside drastically reduced the impact of weather related issues, the amount of “bad bugs” you have to contend with, and the possibility of plant disease developing and spreading.

Is It Had To Grow Vegetables Indoors?

Not at all, it just takes a little pracitce and adapting to a new growing environment. You can start your veggie or herb crops from a seed and grow them year around inside your home.

You may or may not need to supplement natural light with artificial during the late spring through early fall months. Your available natural sunlight and room warmth will be a determining factor when or if you decide to take down or raise your grow lights away from their winter growing height.

When growing indoors year around you must still strive to maintain temperatures and humidity that do not fluctuate. If you love to have your windows open and feel the first slightly warm breezes of spring through a screen door, this habit could cause your plants to become chilled due to the draft and die.

The same seasonal weather and habits change would apply to using an air conditioner or central air during the summer months. Make slight changes to interior home temperature, remaining mindful of maintaining proper humidity if you plan to keep crops growing year round inside the home.

40 Vegetables and Herbs to Grow Indoors

Lettuce	Carrots
Kale	Beets – Sugar Beets
Arugula	Green Onions – Scallions
Red or Yellow Onions	Oregano
Garlic	Potatoes
Ginger	Thyme
Tomatoes – cherry and grape varieties do best	Peppers – bell, banana, jalapeno
Cauliflower	Green Beans
Broccoli	Borage
Radishes	Eggplant
Swiss Chard	English Peas
Spinach	Sprouts and Microgreens – your poultry flocks will love these!
Mushrooms	Amaranth
Rosemary	Parsley
Coriander	Sage
Mint	Tarragon
Dill	Marjoram
Lemongrass	Lavender
Cilantro	Chamomile
Cabbage	Leeks

Make a Plan

As the old saying goes, “failing to plan is planning to fail.” That adage definitely holds true when it comes to growing indoors year round. If you are familiar with outdoor small space gardening, you may have an edge on the rest of us when developing an indoor garden plan.

Unless you have a huge amount of space with awesome outdoor lighting and a pocket deep enough to buy copious amounts of growing lights, you will need to make the most of every available inch of decent indoor vegetable and herb cultivation space.

If this is your first foray into indoor gardening, I highly recommend keeping the crop growing to just one standard folding table and available window ledge space. The plants will need daily inspection and the humidity levels to be kept in check.

While this is not a whole lot of work, it is work and must be conducted both diligently and thoroughly or your veggies will not make it.

First, decide what space you are going to be able to use based on natural window light (even though it will be enhanced by grow lights) heat in that section or the room, as well as humidity.

Once the space has been selected, place your table in the spot to make sure it fits. Next, put all of the growing containers and their drip pans on the table. It will not be until you complete this step that you will truly grasp how much indoor growing space you have.

Growing Containers

I recommend using growing containers in a variety of sizes so you can work them all around the table like they are puzzle pieces. I have been known to place red Solo cups in any void left between planters to make use of that space to grow a single scallion or garlic.

12 Types of Indoor Growing Containers

1 quart to 5 gallon growing pots	2 liter bottle cut in half (with the bottom being saved for growing)
Cottage cheese containers	Sour cream containers
Peanut butter plastic jars	Single water bottle with the middle top removed so it can have holes punched into each end, and string run through to use as a hanging planter.
Plastic buckets	Plastic or paper cups
Coffee cans	Aluminum baking dishes or pie pans for seeds and microgreens
Milk or juice jugs cut in half and the bottom saved for planting	Egg cartons for seeds and microgreens

When all of the planters are in place, you can determine what you want to grow based upon the number and size of the plant containers. It is not until after the table is set up with growing containers that you will know where to best hang your grow light.

Some grow lights, particularly LED ones that must be placed closer to the plants, actually stand on the table so the hang closely over the crops they are shedding light upon.

If you are using table base lamps, make sure to put them on the table with the empty pots before planting so you have left room enough to accommodate the lights, and to make sure they are positioned properly over your growing containers.

Grow Lights

Even if you are blessed with a huge picture window that gets full sun all day, you’re still going to need grow lights to cultivate vegetables indoors during winter months, late fall, and early spring.

The warmth and rays of the sun coming through the window will simply not be enough to keep the plants sufficiently warm and growing.

There are multiple different varieties of grow lights that run from very inexpensive to quite pricey, and boast an equally broad range of light types. 6,400 kelvins is the optimal light to grow vegetables and most herbs. Bulbs of this type, 54 watts, do not eat up a lot of electricity and shouldn’t raise your electric bill very much.

Your vegetables and herbs will require light to photosynthesize – a necessary process to grow and thrive. When plants do not garner enough light, they sprout up overly tall attempting to reach more light and get spindly.

In this type of situation, which can be compounded by either being too close to a cold window without a grow light or when being overly exposed to dry heat, the leaves may not accrue enough energy to grow and form properly – greatly impacting the plant’s yield.

I would highly recommend against relying solely on a window when growing indoors during the winter months unless you live in a coastal area like Florida, or California.

What You Should Know Before Purchasing Lighting

• The photoreceptors in plants are designed to absorb very specific light wavelengths. Grow lights are manufactured to mimic those wavelengths, which is why they and not typical household light bulbs or poultry brooder lights, should be used for indoor winter growing.
• Purchase grow lights that you can safely and easily adjust as the vegetables and herbs grow. The lights should be positioned about 24 inches above most crops when they are seeds or young plants. The lights will need to be raised as the plants grow to avoid scorching.
• Depending upon the variety of vegetable or herb being grown indoors, they will typically require between eight to 10 or around 14 hours of either natural sunlight or simulated sunlight (grow lights) per day in order to thrive. If you plant has a thin stem, a lighter than typical color, or small leaves, it is likely not getting the amount and / or type of sunlight it needs.
• Position your plants beneath the lights according to their needs. Some may need to be placed directly beneath the light while others should be placed on the outskirts of the light’s ray. Florigen is the plant hormone that directs the budding and the flowering process. When a plant receives too much light, the florigen can be killed and prevent blooms from emerging.

Types of Grow Lights

If you have spent any time at all browsing the indoor plant growing lights at stores, in catalogs, or online, you already know how confusing it can be to understand exactly what each type of light is, and which will best suit your year-round indoor garden.

There are six common varieties of grow lights that can be used indoors, but some are only designed to meet the needs of house plants and not garden crops.

1. Fluorescent

This type of indoor grow light tends to work really well for cultivating most varieties or herbs and house plants. If you do not have access to a spacious window with quality and consistent lighting, any vegetables grown beneath them might not flourish.

Fluorescent grow lights are usually the least expensive type of fixture and bulb set you can purchase to aid indoor plants.

2. Incandescent Lights

These lights are also inexpensive and will work decent enough to grow many types of houseplants, but are not adequate for growing herbs and vegetables indoors.

3. High Intensity Discharge or HID Lights

These bulbs are extremely energy efficient and shine way more brightly than most other types of indoor grow lights. A single 1,000 watt HID bulb is capable of generating as much light as approximately fifty 40 watt fluorescent light bulbs.

There are multiple varieties of HID bulbs. Metal halide, high pressure sodium, mercury vapor, and low pressure sodium, are the most common. Metal halide bulbs and high pressure sodium bulbs are the type recommended for indoor gardening, especially in the winter.

The high pressure sodium bulbs cast an orange or reddish hue which is supposed to aid in the flowering of plants. The metal halide bulbs cast a light with a bluish tint that is supposed to help create leaf growth and dwarf the plant.

This type of light could be highly beneficial if growing tomato, green bean, or pepper plants indoors during the winter, early spring, late fall, or when starting a dwarf fruit tree.

4. Compact Fluorescent Lights

These bulbs are both energy efficient and shine brightly. They are far smaller than traditional fluorescent bulbs. They are generally fine to use with about any type of plant. They produce far less heat that either HID or incandescent bulbs which means they can hang a lot closer to plants without scorching them.

What Side Plant Grow Light Do You Need?

Light Size in Watts	Coverage Area	Hanging Height Above Plants
400	With no or low natural light – 5 foot by 5 foot With some or good natural light – 8 foot by 8 foot	1 foot to 4 feet above plants
600	With no or low natural light – 7 foot by 7 foot With some of good natural light 10 by 10 foot	2 to 5 feet
1,000	With no or low natural light 8 foot by 8 foot With some or good natural light – 12 foot by 12 foot	2 to 6 feet

Plants need to have a rest from the light when growing indoors just as they would in their natural environment. In my experience, turning the grow lights on around 6 a.m. and off at 9 p.m. seems to work quite well.

If you work away from the homestead or are going to be out of town, I suggest purchasing a grow light that will accept a timer attachment to ensure the plants both get enough, but not too much light on a daily basis.

Grow in Spaces Without Natural Light

The short answer to this question is yes – but it will take a lot more work. The occasional news alert that someone was busted for growing pot in a closet, basement, or in their bathtub proves plants can grow in a space that is completely absent of natural sunlight – but doing so is going to take a lot more work and money.

The crops’ only source of light will be artificial, so you will have to invest in top quality and more grow lights than you would if growing elsewhere in your home. LED grow lights are recommended because they can be lowered close to the plants without producing scorching and help keep the crop warm but not hot while providing light.

Plastic or reflective insulation is also typically highly recommended when growing in a dark area so the artificial light the plants are sustaining themselves on can all be directed towards them.

On the up side, growing in such a confined and dedicated space can make it easier to control humidity.

When growing without any natural light in a closet, basement, garage, etc. you should invest in a hygrometer to test humidity at least once a day.

Ventilation fans are essential when growing in a confined space. Attempting to do so without one will almost surely result in total crop failure.

Temperature

Keeping a steady and proper temperature is essential to your winter indoor growing operation. Plants are typically highly sensitive to fluctuations in temperature.

To ensure your greatest chance of success, take the time to learn about the temperature needs and weaknesses to environmental changes for every vegetable or herbs you are growing.

Some, like basil, are so sensitive to even slight changes in temperature that being placed in the draft of a door can kill them within mere days. Garlic, potatoes, kale, onions, beets, and carrots, on the other hand, are far more hardy and less likely to be greatly impacted by a door draft or close placement to a window.

Attempt to keep the room temperature between 65 and 75 degrees F (18 to 23 C) for best results in your indoor winter garden. A slight change in temperature of even 10 degrees in either direction can harm plant growth, or kill the ones that are more sensitive to such environmental changes.

If a plant has gotten too hot and likely also not exposed to enough humidity, it will be tall and spindly or short and have a weak stem. Plants that have become chilled usually develop yellow and drooping leaves that will ultimately fall off.

Humidity

The humidity needs of each vegetable or herb that you are growing will likely vary at least slightly. If you grow vegetables and herbs indoors that you can also cultivate in your agricultural growing zone outdoors, odds are that the needs of the plant are similar enough to not require a lot of math to keep humidity at acceptable levels for the entire winter garden.

If you have a fireplace, wood stove, or even a propane gas wall mount heater keeping your home warm in the winter, struggles with dry heat are probably already commonplace.

We stopped using central air in our home about seven years ago, but we do keep a single window air conditioning unit in the bedroom to cool it down for evening a few weeks out of the year.

If you have window air conditioning units or run a central air system in your home during the warm weather months, you will have to also pay keen attention to dropping humidity levels and the possibility of some plants becoming too chilly – causing stunted growth.

There are several simple and free or inexpensive ways to keep infusing some moisture in the air and keep humidity at the proper level and largely consistent.

• Place a kettle or pot of water on your wood cook stove to infuse some moisture and humidity into the air.
• Place a pie pan with lava rocks or bricks on the indoor winter garden table to generate a larger evaporation source right next to the plants. While this works, it will take up some space on your growing table that you might not want to lose.
• Huddle plants close together to encourage a rainforest style effect to trap and house moisture.
• Spritz the plants daily from top to bottom so the water on the plant is churned into moisture. This works best, in my opinion. Always spray the plants during the early afternoon or late morning so the water has time to evaporate and the plant dry thoroughly before the grow lights are turned off for the evening. I tend to overwater, so the spritzing not only helps me add humidity to my indoor winter growing operation, but also serves as their watering. Be careful when watering plants with fuzzy leaves or stems, they can trap water too tightly, and cause mildew or plant disease to form if they do not have time to dry out completely each day.
• Purchase a humidifier, and place it near the indoor winter garden to keep the humidity levels better regulated and consistent.

Keeping humidity levels high enough is typically the most difficult indoor winter gardening challenge.

If you notice any of these signs developing on your plants, you likely have a low humidity issue that needs to be resolved immediately:

• Plants that are losing their leaves.
• Plants which boast a puckered or withered look.
• The tips of the leaves on your plants are turning brown.

Ventilation

Your vegetable and herb plants will also require proper air flow in order to flourish. Maintain a steady airflow between the plants and in the room so it does not get “stuffy.” Some indoor winter gardeners like to run a small fan to add extra ventilation into a small growing room or space.

Also, the week prior to moving any plants outdoors if they are still producing when spring arrives, you may want to run a fan lightly during daylight hours to help harden them off so they transition well from a likely warmer indoor environment to a cooler outdoor one.

Planting Medium

Indoor plants, even more so that outdoor plants, greatly benefit for a quality growing medium. You can use quality compost from your pile or rich soil from your growing plots, but doing so can bring unwanted bugs into your home and indoor garden.

Unlike when growing outdoors, you will not have the benefit of having good bugs around to eat the evil ones. Yes, insect pests are still going to be a problem even though you are growing indoors and through the winter when snow can get hip deep outside.

White flies are one of the biggest problem insects you will likely encounter when growing indoors. This is why you will still need to use insecticide on your crops and should opt for manufactured seed starter soil when planting your indoor garden.

The planting medium should be both loose and well draining, but should also boast enough natural organic matter that the soil will maintain nutrient levels and moisture. As noted above, battling moisture levels could kill your indoor garden crops – especially during the winter.

Indoor Garden Planting Tips

Make sure to drill or poke drainage holes into your indoor garden planters. You can use manufactured garden planters. I purchase mine for pennies on the dollar at the end of the summer sales, or upcycle containers you have around your homestead.

I use every inch of table space when I grow indoors. This means I place paper or plastic cups in between any void left on the table between planters, use a ledge behind the table and the windowsill to grow crops (onions usually because they can withstand the colder temperature by the glass) egg cartons for starting seeds, cottage cheese containers, etc.

Growing plants that can be cultivated in small containers on wall shelves is another superb space saving auction.

You should also strive to keep your planting area clean and dry by placing a drip tray of some type beneath each planter. You can purchase cheap plastic ones at big box stores or garden centers, use plastic container lids, aluminum pie pans, or one of my personal favorites – baking sheets from the Dollar Tree.

Fertilizing

You may need to fertilize your indoor window garden on a weekly basis. I tend to do this only once or twice a month with most plants, but tomatoes and others that are sensitive to humidity fluctuations tend to need such treatments more often.

How to Make Compost Tea

1. Fill a 5-gallon bucket one-third full with quality compost.
2. Fill the bucket the rest of the way up with room temperature water.
3. Allow the water to filter through the compost for at least 3, preferably 4 days at or near room temperature for best results. Some folks only let the compost brew for a few hours. Do not permit the brewing compost tea to freeze.
4. Strain the compost tea through a mesh screen, canvas, or cheesecloth to strain away solid organic matter – keeping the liquid.
5. Add in more room temperature water and stir the mixture until it resembles a typical tea in color and consistency.
6. Gently pour the tea around the base of the plant, and the top of the soil in the container.

Watering

Crops being cultivated indoors tend to dry out more rapidly than those grown in the ground or outdoors. Be prepared to water your plants more often than you would outside, expect when watering garden plants during intense dry periods.

When watering indoor garden plants, always use room temperature or Lukewarm water and not hot or cold water – that would shock the plants. While water might run out of the pot and through the drainage holes into the drip pan, but do not allow it to accumulate there or it can lead to root rot and other plant diseases.

Touch the soil on a daily basis to determine if it feels dry, moist, or overly wet before watering again.

Over and Under Watering Warning Signs

Over-Watering Signs	Under-Watering Signs
Wilting along the stem first that spreads out to the leaves	Wilting along the outer tips of the leaves
Overall discoloration of the plant	Brown, discolored leaves
Wilting foliage	Flowers or leaves falling off the plant
Leaves drooping or falling off	Dry soil
Stunted, stalled, or stopped growth	Wilting on the entire plant

Hydroponics

You can also nix soil growing and opt to create a hydroponics indoor winter garden. Some folks who prefer to cultivate crops in this manner staunchly maintain that they experience up to 50% faster plant growth than when cultivating crops in soil.

When growing in a hydroponics environment the roots of the plant are not bound up in the soil, and therefore have direct access to the nutrients being provided. Hydroponic growing does not typically require larger containers to grow bushy plants like is needed when cultivating in soil.

Seed Starting

Many homesteaders use their window indoor garden as a means to not only extend their growing seasons but to maneuver their growing their own groceries operation continuously from spring, to summer, through the fall and winter and back again.

This means you may be starting seeds outdoors in the summer so they have a vibrant start and continue to grow into plants indoors – or start seeds in the late winter or early spring so you have nice large plants to transplant into your garden.

Starting seeds outdoors could greatly help get your indoor winter garden off to a healthy start. Having the benefit of warm temperatures and robust natural sunlight can help the seedlings grow at an appropriate rate of speed and to fill out strongly before transitioning to primarily artificial light and manually adjusted humidity.

Growing Microgreens Indoors

If you do not have much indoor growing space or want to make the most of every inch you have, consider growing microgreens. They require a shallow growing container that only has to be 2 inches deep – with proper drainage holes in the bottom.

The seeds are simply sprinkled densely onto the surface of the soil, and then covered with a light layer of dirt. Microgreens prefer to grow in full sun, which makes them perfect for window sill placement.

It takes only a couple of days to at most a week for the first leaves to emerge on microgreens. Once the microgreens have two to four full leaves and have opened up, they are ready to harvest.

These tasty little greens are mature when they hit about one and a half to two inches tall – with the exception of pea and sunflower microgreens which need to reach three to four inches tall before harvesting.

Transitioning Plants

You surely do not need to move plants from your indoor garden outdoors so they continue to flourish, but if you choose to do so, it has to be done properly or they will die within days. Both seedlings and plants must be hardened off before they can be transitioned outdoors after being grown inside over the winter months.

Simply removing them from an indoor growing table out into a much colder environment will not allow the plants to have time to spurn a cuticle thick enough to be able to withstand the new and more harsh environmental conditions, or to prevent water loss.

Taking the time to acclimate your seedlings and plants to their new environment will results in better continue growth and yield.

How to Harden Off Indoor Garden Plants

1. About one week to 10 days before the planned relocation of the plants, put the outdoors in a cold frame or a spot that is primarily shaded for about three hours.
2. For the next two days, increase their exposure to the great outdoors by one to two hours.
3. On the following days, put the plants in a spot where they are certain to garner morning sun, but move them back into the shade during the afternoon hours.
4. Once the temperature continues to hover around 50 degrees F (10 C), the transitioning plants should be strong enough to withstand evenings outdoors.
5. When transplanting on day 7 or 10, place some quality compost into the hole, then the plant, and another light layer of compost or mulch – or a combination of the two, around the base of the plant.

It is best to transplant on a day that is not very sunny and to lightly water each plant after it is placed in the ground. You can also leave your plants in their containers if you do not want to garden in a raised bed or traditional ground plot.

Moving Plants Indoors

At the end of the summer or fall growing season, transition them out of direct sunlight and into a partially shady and then shady spot over the course of three to five days before relocating them into your winter indoor garden.

Most Common Indoor Plant Insect Pests

• White Flies
• Aphids
• Scale Insects
• Caterpillars
• Thrips
• Spider Mites
• Earwigs
• Root Mealybugs
• Eelworms
• Cyclamen Mites
• Earwigs

Most Common Indoor Plant Diseases

• Dampening Off
• Root Rot
• Sooty Mold
• Powdery Mildew
• Rust
• Botrytis Leaf Spots
• Black Leg

Keeping a Close Eye on Your Indoor Garden

The best way to ensure your crop cultivation over the cold months of winter is a success is to do a visual inspection of the plants and growing conditions on a daily basis. This process shouldn’t take more than 10 minutes and will allow you to spot signs of trouble before it is too late to save your plants or entire year round indoor garden.

Keep your eye out for signs of damage caused by spider mites and white flies, these are the two most problematic pests that an indoor grower or greenhouse typically has to contend with on a regular basis.

You do not want an infestation of white flies partying around either your indoor garden or Christmas tree – they will take far longer to get rid of than the daily visual inspection of your plants would have.

I sprinkle a 1 to 2 mixture of standard table salt and flour together and LIGHTLY sprinkle on plants to keep insect pests away. I recommend using this practice at night when you are turning off the lights to avoid any scorching of the plants caused by the combination of artificial lighting and the table salt.

I only use natural and homemade gardening aids outdoors, and follow the same routine indoors. In addition to the compost tea, you can also use coconut coir and vermiculite in or on top of your soil to help it maintain optimal quality.

There are some finite rules when gardening indoors during cold weather months, but none that are extremely time consuming or difficult to follow.

Once you develop your indoor gardening cultivation habits you will quickly fall into a routine that should breed great success when it comes time to harvest freshly picked vegetables and herbs that you grew yourself… while singing Christmas carols and watching the snow fall outside.