How to Grow Carrots in a
Hydroponic System

by Bob Kowal
(Spokane WA)

HOW do you grow carrots in hydroponic gardens? I want to grow some inside and would like to know the best equipment to get started with doing that.

Also, I am writing a book to help teachers teach science easier and would very much like your permission to use the diagram Life Cycle of a Plant in the book. I will reference your site and tell readers to go visit it for the awesome info on hydroponic gardening.

May I have your permission to use the diagram? I love seeing a young man getting involved in science - good luck to you, Bob Kowal, Simplification of Science

Answer:  Bob- you absolutely have my permission to to use any of the images from my site in your book. Now let's talk science!

A hydroponic system supplies plants with three basic things....water, nutrients (in the water), and oxygen (at the root level). Systems can be modified or adjusted to accommodate the growth habits of a particular crop, but these three basic needs must always be met.

Water is easy enough to provide. Most tap water will do, though it is a good idea to let it sit out overnight to de-chlorinate and also to come up to room temperature. This helps prevent damage from temperature shock.

Oxygen at the root level is important because nutrient absorption only occurs in the presence of oxygen. Any hydroponic system in which the plants are NOT grown directly in standing water will automatically provide enough oxygen to the roots. When plants ARE grown directly in standing water, an air bubbler is used to keep lots of oxygen dissolved in the nutrient solution. It is important to note, however, that some plants simply do not like "wet feet". This is one reason it is important to know the growth preferences of your plants before you settle on a particular hydroponic system.

As long as you know how to maintain a nutrient reservoir properly (see how to grow hydro), providing nutrients to your plants is a simple matter of knowing their nutritional requirements. Carrots, for example, prefer a pH of about 6.3 and a nutrient solution strength of 1120-1400 ppm (16-20 CF). It is important to add that they are started out on a weaker solution at first.

Root crops need lots of room to grow. This is especially true with carrots. Carrots need to be "thinned out" in a hydroponic system just as they need to be when grown in soil, and for the same reasons. Over-crowded carrots will fork, grow deformed, and wrap around each other. They also will not grow as large as they should. If the container is not deep enough, the carrots will grow sideways when they hit the bottom. Root crops like potatoes and carrots need a light weight, loose grow medium that is easy to "push out of the way" as they grow. Finally, root crops should not be grown in directly in standing water....they tend to rot when they are kept too wet.

With all of this in mind, there are a couple of good strategies for growing carrots hydroponically. One is to use 12 inch flower pots filled with perlite or a mix of 2 parts perlite to one part vermiculite (to retain the moisture better). These pots can be hand watered from the top two or three times a day, and can also be placed in a container with a half inch of nutrient solution. The perlite tends to draw moisture up from the bottom, but also maintains a lot of oxygen within the medium. This meets the needs of the plants in a simple fashion. The same thing can be accomplished in a more automated form by adding a small water pump, a few drip emitters, and a digital timer.

Another system for gardening carrots and potatoes is very similar to the above, using 32 liter plastic storage totes filled with plain perlite. Several 1/4 inch holes are drilled into the containers 3 inches up from the bottom. This allows 3 inches of nutrient solution to stand in the bottom, which the perlite constantly draws up into the rest of the grow medium. Again, the container can be hand watered from the top a couple times a day to maintain moisture in the top layer, or a drip system can be set up with a small water pump and a timer.

The storage tote system has been used for at least two years with very good results. Once you know the basic requirements of the plants you are growing, it enables you to make changes or improvements to your hydroponic system without fearing bad results.

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AffordableGarden Design&Setup

(10 week update below)

Find out the cheapest and easiest ways to garden productively in this article.

Hi everyone, Jason from Jason's Indoor Guide here. When I got started with hydroponic gardening more than 24 years ago, my first garden used rockwool cubes and B.C. Nutrients....and I remember thinking to myself yeah, sure, there may be a lot of advantages to gardening with hydroponics, for example there are very few pest problems, therefore very little pest control, no weeding, no plowing or tilling the soil, no soil testing or having to add things into the garden soil, no watering the garden....but for someone who just wants to grow their own vegetables and have more control over their food supply and the quality of the food that they eat, the cost of constantly having to buy grow media and hydroponic nutrients makes this an expensive hobby for most people...

Epic Nutrient Change

I suppose when you take into consideration how much money you save NOT having to buy food at the grocery store, it is surely cheaper to grow your own food hydroponically even with the cost of high quality nutrients. Nevertheless, I didn't have a whole lot of money to work with and I needed to make my efforts as affordable and effective as possible....and in the last 24 years I HAVE learned a thing or two!

As you browse through Jason's Indoor Guide, you will notice all of the systems that I use personally are homemade systems. As I got 3 or 4 years of experience under my belt, I quickly adopted a preference to standing water systems and systems that use expanded clay pellets or lava rock, because the media is re-usable and it eliminates a huge operating expense. So once a hydroponic system is built, garden maintenance is minimal- check and adjust the nutrient solution daily, and to change it completely every 2 weeks....and the biggest operating cost is the hydroponic nutrients. (and the electric bill, lol)...

Homemade Cloner

And, regarding the cost of the nutrients....I experimented for about 3 years with making different compost teas and nutrient teas, but there is still a lot of expense $$$ associated with making high quality nutrient kelp meal, liquid seaweed, rock dust, bat guano, un-Sulfured molasses, worm castings. You can eliminate a lot of this expense by becoming an expert at making high-quality colloidal humus compost, and use your properly made compost as the basis of your hydroponic nutrient solution.

Unfortunately, I have been gardening for over 24 years and I have only just recently mastered this difficult skill....and even then, only because I happened to find a very easy to follow, high quality technique and decided to follow the instructions to the letter. I produced more high quality compost in just one week than I was able to use in a whole year! If you can master the technique, I highly recommend it. It is one of the top 3 things you can do to increase the productivity of your food production efforts, while at the same time decreasing the amount of effort required to grow all of your own food, and decreasing the total cost of operating your food production system.

And when I say decrease operating costs, I mean decrease them to almost ZERO, especially if you are producing your own nutrients...

High Efficiency

The ultimate solution to eliminate the cost of your hydroponic nutrients: Imagine a hydroponic system that does not require you to buy any nutrients, does not require you to make your own compost, and does not require you to brew your own nutrient tea. Seriously! No cost and no effort as far as providing nutrients to your plants! Plus, at the end of the gardening cycle you harvest all of your garden vegetables, PLUS YOU HARVEST FISH from the system--->


Click Here to learn more!

This solution is aquaponics. If you are serious about producing all of your own food and being self-sufficient, this is the ultimate solution for reducing expenses (as much as possible), reducing the total amount of work required, and maximizing the productivity of your gardening efforts. I have been gardening for over 24 years, and it is the perfect food production solution in my opinion.

Produce garnden vegetables AND fish together. Eliminate fertilizer costs!

Besides mastering how to make high quality compost, learning aquaponics is one of the top 3 things you can do to increase your garden productivity, reduce your total costs, and reduce your total work. The product that I learned from is called Aquaponics4you. With all of my hydroponic gardening experience, the first time I came across the Aquaponics4you product I knew immediately that it was something very special! Place an aquaponics system outdoors and use the sun instead of grow lights, and you have reduced every garden expense to nearly ZERO!

The Same System/ 10 Weeks Later!

If you've found this site helpful at all, I would really appreciate it