Introduction: How to Start Growing Indoors

About: I have a degree in Electronics Engineering and various certifications in all kinds of internet programming languages. Professionally, I have over 20 years of experience in various roles including an electronic…

If you’ve ever wanted to grow plants such as herbs, greens, strawberries, and tomatoes at home but thought it would be way too hard and expensive, then you’ll want to read on. You’ll still need to learn some plant care basics, but here are some handy tips and tricks.

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Step 1: What Plants Need

Let’s talk about what your plants will need on a continual basis to successfully grow indoors.

Water quality can be a problem in hydroponic systems. Water with excessive alkalinity or salt content can result in a nutrient imbalance and poor plant growth. Softened water may contain harmful amounts of sodium. Water that tests high in total salts should not be used. Salt levels greater than 0.5 millions or 320 parts per million are likely to cause an imbalance of nutrients.

Oxygen: Plants require oxygen for respiration to carry out their functions of water and nutrient uptake. In soil adequate oxygen is usually available, but plant roots growing in water will quickly exhaust the supply of dissolved oxygen and can be damaged or killed unless additional air is provided. A common method of supplying oxygen is to bubble air through the solution.

Mineral Nutrients: Green plants must absorb certain minerals through their roots to survive. In the garden these minerals are supplied by the soil and by the addition of fertilizers such as manure, compost, and fertilizer salts. The essential elements needed in large quantities are nitrogen, phosphorus, potassium, calcium, magnesium, and sulfur. Micronutrients – iron, manganese, boron, zinc, copper, molybdenum, and chlorine are also needed but in very small amounts.

I’m sure you’re already familiar with growing plants in soil, so I won’t discuss the obvious need for soil in containers. However, If you want to try hydroponics and maybe even aquaponics read-on, otherwise, skip ahead.

Step 2: ​Support Your Plants

Support your plants by giving the roots something to grab onto and hydrate as needed.I recommend starting seeds with coco-coir (pronounced coyer) and then expand into clay pellets as the medium for containing your plants’ roots. Also known as LECA (Lightweight Expanded Clay Aggregate), or common brand name: “Hydroton,” clay pellets retain and release moisture at a slow, constant rate so the roots aren’t over- or under-saturated.

Step 3: Nutrients

Recommended Equipment:

A nutrient solution system: I recommend starting with General Hydroponics Flora Series Performance Pack, consisting of the main three liquid parts, several enhancements, and the pH test kit. (Handy tip: If you ask General Hydroponics or other nutrient solution vendors for samples of their products, you can usually get free or discounted trial sizes.) A word of caution about miracle growing fertilizers, do not add any fertilizers other than those you know to be hydro-friendly, as it can cause a nutrient build-up harming your plants.

The nutrient solution water level of the hydroponic container system must be monitored.

As the nutrient solution level decreases it needs to be replenished with fresh water, otherwise the nutrient solution becomes more concentrated and some plants won’t respond well. Add fresh water to bring the concentration back to the level it was when started, often referred to as “topping-off.” The pH of water is an important measurement whether you are gardening indoors or outdoors, soil or soil-less, because it affects whether a plant can properly take in nutrients. The electrical conductivity (EC) of water estimates the total amount of solids dissolved in water -TDS, (Total Dissolved Solids). TDS is often measured in ppm (parts per million). In hydroponics, this measurement is used to determine the approximate concentration of nutrient solution to water.

There is no need to adjust your pH or EC until it is necessary.

There is a lot of misinformation out there about keeping the pH and EC regulated. If I were paranoid, I’d say it was a conspiracy from hydroponics manufacturers and retailers who want to sell more consumable product. Don’t get me wrong, proper pH and EC is important, even critical, to the success of a plant.

I recommend a handheld pH tester such as the Oakton EcoTestr pH 2 Waterproof pH Tester, which is excellent for the home gardener and has been proven time and again to be accurate. There are many hand-held EC devices available as well and if you are checking the pH, it’s a great time to check the E.C.

When do I need to adjust the pH?

Only under the following conditions:

pH is at or below 5.0 or above 6.5

AFTER at least 30 minutes from the time of topping-off or changing the nutrient solution.

How to adjust?

I highly recommend using pH Up and pH Down from General Hydroponics sparingly and only when necessary.


Flushing means to literally flush empty the nutrient solution from the hydroponics system and replace it with fresh “good” tap-water. Then return the nutrient solution back to what it should be for the phase of growth. When in doubt, flush the system and refresh the nutrients. Otherwise, it’s recommended to flush your recirculating system every 7 – 14 days. When I grow, I try to keep the nutrient solution working as long as possible, however, salts build-up over time and it is good to flush with fresh water from time to time.

Step 4: Containment

Hydroponic gardening doesn’t have to be scary or a laboratory experiment! Consider starting out with either Emily’s Garden and/or the General Hydroponics Drip Ring Kit

The simplest and most common hydroponics system is a DWC (Deep Water Culture) system which consists of a plastic container acting as a reservoir for the nutrient solution with or without an air-pump while the roots hang down into it. You can even make your own from an old bucket and an aquarium water pump in a pinch. Here are some cost-effective methods for starting your own hydro system.

Recirculating Drip Systems options

Recirculating systems are very inexpensive, modular, and very effective. The recirculating system is the same as a DWC (Deep Water Culture) system, with the inclusion of water being pumped over the rooting medium (typically clay pellets). The best systems use a single air pump to both aerate the nutrient solution and pump the water up over the rooting medium. Let’s take a look at our options…

Drip System Options

I’ve distilled the recirculating drip system for hydroponics down into the following options:

Start with one module completely off-the-shelf: General Hydroponics Complete Single WaterFarm Kit or dive immediately into a complete system that is completely off-the-shelf: General Hydroponics Complete 8-pack WaterFarm Kit

Most economical choice is a DIY Drip System partially off-the-shelf:

  • 5 gallon bucket ( new, or thoroughly cleaned ) with lid ( cut holes in the lid )
  • or hydroponics bucket lid basket (various sizes)
  • aquarium air-pump ( 1/4" vinyl tubing comes with their kit: )
  • General Hydroponics Farm Kit

Assembly Instructions

“Upcycle” plastic containers

Plastic lidded storage totes are typically used to make DIY DWC (Deep Water Culture). There many tutorials on this topic, so I won’t replicate them here. My latest version uses an empty plastic kitty litter container. Reusing plastic containers to make simple hydroponics systems is by far the least expensive way to get growing. When reusing containers consider that there is a possibility that the plastic will break down over time and may leach into the system. Also, be judicious about which types of containers you choose to reuse. I feel that the kitty litter container is safe enough after being thoroughly cleaned, but obviously any container that once held anything toxic should be recycled appropriately.

Step 5: Indoor Tent or Room?

Important factors to consider include:

  • How much space do you have?
  • What do you want to grow and and how much of it?
  • What is the cost of equipment and how much time do you have to spend maintaining the system?

Regardless of which method you choose: soil, hydroponic, or an aquaponics system, none will be able to compensate for poor growing conditions such as improper temperature, inadequate light, or pest problems.

Indoor grown plants have the same general requirements for good growth as field-grown plants. The major difference is the method by which the plants are supported and how the inorganic elements necessary for growth and development are supplied. Plants grow well only within a limited temperature range. Temperatures that are too high or too low will result in abnormal development and reduced production. Warm-season vegetables and most flowers grow best between 60° and 75° or 80° F. Cool-season vegetables such as lettuce and spinach should be grown between 50° and 70° F.

recommended equipment:

48” x 48” x 84” indoor grow tent

24” x 24” x 48” indoor grow tent

Setup a tent, or closet, or spare-room.

A search on Amazon will result in many options and many sizes. Whatever size of tent you think you have space for, imagine the tent taking up a little more than that and reconsider. Trust me, I’ve made this mistake more than once.

Step 6: ​Electricity for Ventilation and Lights

Recommended Equipment:

Electricity is needed to operate fans, pumps, and lights. It is a very good idea to use a GFCI adapter for your AC outlet if it does not already have one. Good quality extension cords can then be attached.


Recommended Equipment:

Where can you get fresh-air and where is it acceptable for the exhaust to blow? When purchasing a ventilation fan or blower for the setup you will want to get some ventilation duct tubing as well. I highly recommend some air filter material over your intake to prevent unnecessary contamination ( pet dander )


All vegetable plants and many flowers require large amounts of sunlight. Hydroponically grown vegetables like those grown in a garden, need at least 8 to 10 hours of direct sunlight each day to produce wells Artificial lighting is a poor substitute for sunshine, as most indoor lights do not provide enough intensity to produce a crop. Incandescent lamps supplemented with sunshine or special plant-growth lamps can be used to grow transplants but are not adequate to grow the crop to maturity. High intensity lamps such as high-pressure sodium lamps can provide more than 1,000 foot-candles of light. The serious hobbyist can use these lamps successfully in areas where sunlight is inadequate. The fixtures and lamps, however, are very expensive and thus not feasible for a commercial operation.

Recommended Equipment:



The relationship between the output of grow lights typically focuses only on wattage. The more wattage in your cottage, the more power consumption and more photons available for the plants to absorb proving better plant growth. The caveat being that the more power consumption, the more heat is produced and the more ventilation that will be necessary in order to maintain a comfortable growing environment.

Step 7: Garden Maintenance

❏ Air Circulation and Ventilation: Proper circulation will prevent dead zones of bad and/or cold
air at lower levels and hot layers of air near the ceiling.

❏ Check top and underside of leaves for likely signs of disease, insects or nutrient deficiency.

❏ Prune regularly. Promptly remove and dispose of any dead, dying or diseased foliage in the growing area. Conduct any necessary shaping, training, or stressing of branches and ensure foliage is properly supported (via string, netting or stakes).

❏ Check Lights: Maintain lamps 12­-36 inches above plants! Check timer is correctly programmed for the given phase of growth. Check electrical connections/plugs.

❏ Check for signs of leaf burn on foliage closest to the lamp.

❏ Rotate or turn plants as needed to get uniform growth. Ensure oscillating fans are covering all foliage, especially those closest to the lamp.

❏ Check for signs of insufficient light, e.g. sparse, spindly foliage. Ensure foliage is not being unduly shaded by other plants.

❏ Check for plumbing leaks; pooling in trays/channels/pots.

❏ Check drainage and/or feed outlets (drippers) are not being blocked by roots.

❏ Check roots/medium at various points for signs of disease, rotting or molding materials, insects or over/under watering.

❏ Check pumps and timers to ensure they’re working properly. Ensure nutrient schedule appropriate for the current phase of growth.

❏ Recirculating systems: Discard and replace old nutrient every 7­-14 days.

❏ Conduct optional foliar spraying and apply optional additives, e.g. compost tea.

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Brave the Elements 2016

Participated in the
Brave the Elements 2016

Indoor Gardening Contest 2016

Participated in the
Indoor Gardening Contest 2016