By Peat
Growing Carrots Hydroponically
Submitted on Sat, 2008/11/15 - 6:55pm
Last updated on Mon, 2009/03/30 - 5:39am
Carrots and subterranean vegetables can be grow hydroponically as well, hydro is not just limited to above soil growth.
What you will need:
Perlite
Vermiculite - add to perlite for better water retention, not absolutely necessary but it does help.
A good deep, ideally lightproof plastic container with holes at the bottom - at least 12 inches deep and the same wide. The bigger the better.
Another plastic container that the one above can sit in, this will hold a quantity of water all the time. Alternatively, a deep drip tray - say 2 to 3 inches in depth.
Fill your container with perlite, ideally you would add vermiculite to this as well - the ratio is 3:1 perlite to vermiculite.
Place your seeds in the main container, cover with vermiculite to the depth that is written on your seed packet.
Lightly mist/spray the top of your main container with some water, we need to get some water to the seeds to start. Keep the top of the main container moist, keep misting as appropriate until the seeds establish themselves - see your seed packet for germination times.
Don't pour water directly down on them at this phase, the seeds will be washed away by this!
Once the seeds have germinated, give the top of this container a good watering three times a day - approx.
Keep the drip tray (or other container), full of water
Generally - carrots take 2-3 months to mature and germinate in 6 to 10 days.
Radishes are also a good crop, they need less space and grow really quickly. They will mature in 30 to 40 days and germinate in 2 to 6 days.
Enjoy the world of subterranean hydo... 
Weekly Pictures
(2 votes)
Sun, 2008/11/16 - 1:37pm
#2
Only with radishes, and that was way back in time...
The same principle is applied to carrots as well, you are basically replacing your soil with perlite and hydro chemicals, plus a little light...
Oh well, as I made this a 'grow log' then I suppose I should do this sometime. I'll see what I can rustle up, I don't have any perlite/vermiculite at this moment in time so I will have to see about getting some.
Call this work in progress then...
Sun, 2008/11/16 - 2:01pm
#3
LOL! Don't feel compelled. 
Thu, 2008/12/04 - 2:26pm
#4
The perlite and vermiculite have been ordered, I already have a 12" pot and drip tray, the carrot seeds will be bought tomorrow.
I will use the spillover light from one of my aerogardens, pictures and results to follow...
Thu, 2008/12/04 - 2:49pm
#5
Looking forward to seeing this! Are carrots a low-light species?
Thu, 2008/12/04 - 3:11pm
#6
Not really, they do need full sun. But, they can tolerate partial shade - although they won't be quite as developed.
I just hope the AG spillover light is good enough for them, it's better than the winter window light! It's all about experimenting, nothing ventured, nothing gained?
Mon, 2008/12/08 - 4:16pm
#7
The carrots are now planted in the perlite/vermiculite mix, ratio of 3:1
They have been put in a 6 inch pot, I didn't want to use the 12 inch one as this would be a waste of these growing mediums if this did not succeed - let's see how they grow in the 6 inch one first...
The perlite/vermiculite were mixed, put in the 6" pot and then soaked with normal water. The carrots (Early Nantes 2, www.thompson-morgan.com/seeds1/product/345/1.html) were selected due to their quick harvest time and length.
The carrot seeds were sprinkled over the top and a layer of vermiculite put over them, they were misted with water as I did not want them being carried to the bottom of the pot if they were watered normally. A piece of cling-film was put over the pot to aid germination, and the whole container placed directly under the AG bulbs. The bottom of the drip tray was filled with water, this will wick up through the pot due to the properties of these two growing substances.
Carrots
Carrots, Cucumber & Strawberries sharing the light
Mon, 2008/12/08 - 5:00pm
#8
Looking forward to seeing the result of this!
Do you have any reflective blanket, btw? I added a bit on the side of my pro100 as a drape over an outrider, and the plants definitely responded to the increased light. (Did that make sense? Outrider next to pro100. Bit of silvered blanket from top of lights, slanting out to far side of outrider. So light scatters to that side and is reflected down onto outrider.)
Mon, 2008/12/08 - 5:45pm
#9
I remember your reflective blanket experiment from before.
What I have around mine are pieces of cardboard covered with silver foil, this reflects a good amount of light back onto the plants. I'm running out of AG's now, how many plants can one grow from the light of one garden?
Mon, 2008/12/08 - 8:04pm
#10
how many plants can one grow from the light of one garden?
Yes, that's what we're trying to figure out now. Surprisingly, the spot between my two minis seems to get enough light, probably because the minis are very short. I think one of my nextgen outriders will go there. The spot next to the pro100 is certainly doing better now, but maybe still isn't enough. The Deluxe would have gobs of spillover light if the hood wasn't up near max.
Is it possible to put your two AG's next to each other and put spillover-dependent plants between?
Tue, 2008/12/09 - 12:48pm
#11
Unfortunately I cannot get them together, they reside at opposite ends of my kitchen on the workspace, and are separated by the walkway in between. I could combine them if I moved them away from the window and into a corner somewhere, but, I would rather get some outside light to them - there is still the occasional day with bright sunshine, for what it's worth.
I have just planted thyme and rosemary seeds in separate 3 inch pots now, they are standing on the remaining space to the right of my cucumber. So, that's carrots, cucumber, thyme, rosemary and strawberries - not bad for one AG eh?
Tue, 2008/12/09 - 5:58pm
#12
Wow, that's using everything you have, good job. What are you going to do in a week when the cucumber takes over, use them for support?
Mon, 2008/12/22 - 12:11pm
#13
Week 2
No week 1 due to me being away.
I seem to have had near 100% germination from the seeds I planted, better than I ever expected.
The little seedlings are getting misted every morning and in the evening after work (just misted before this photo), the pot is still directly under the AG lights which is helping immensely.
Mon, 2008/12/22 - 12:19pm
#14
Looking good! How many carrots about will you thin this to?
Mon, 2008/12/22 - 12:28pm
#15
I haven't decided how many I want in the pot yet. They are supposed to be thinned to 4 inches apart, the ones I pull will be put in another pot - I hate cutting good seedlings down.
Mon, 2008/12/22 - 3:42pm
#16
Nice job, Peat. It hurts to thin, doesn't it? Where are you going to put another pot of carrots? Train the cukes to hold 'em!!
Mon, 2008/12/22 - 5:11pm
#17
The way those forming tendrils are clinging on, I think they could support another couple of pots... 
Mon, 2008/12/22 - 5:22pm
#18
This is a very cute image, the cucumber tendrils holding littler pots. 
Mon, 2008/12/22 - 5:35pm
#19
Drat, I cannot find that photo I found some time ago. Someone had trained their cucumber to hold a pen, it gripped it really well and looked so funny. 
Mon, 2008/12/22 - 5:36pm
#20
You'll just have to train your own and take a picture of it.
Sun, 2009/01/04 - 5:54pm
#21
Week 4
No problems so far, the plants really could do with thinning out and re-planting (what I can salvage), in another perlite/vermiculite pot.
Week 3 missed as I was away again!
Sun, 2009/01/04 - 5:58pm
#22
Have you tugged any up yet to see how long the carrot is?
Mon, 2009/01/05 - 1:40pm
#23
I will probably do this tomorrow, we have been away for New Year and only got back tonight. Playing catch-up again, sorting the plants out - the tomatoes nearly ran dry, and posting here.
I was a little worried about the cuke, but it did not drink too much water so was fine. I'm going to have to get a large black plastic container to put my plants in in future, the AG just does not have the capacity for periods away.
Edit: Re-potted and thinned out the carrots today, the roots are about 1 inch long.
Mon, 2009/01/05 - 2:35pm
#24
Oh, how cute! Did they taste good, these 1" carrots?
Tue, 2009/01/06 - 12:42pm
#25
They tasted great, took about 100 of them to before I noticed though.
Only another 1900 to plant out now! Suddenly, the year is looking busy...
Tue, 2009/01/06 - 6:11pm
#26
Admin: Moved a bunch of comments to new topic Seed-Starting Lights, rather than continue to clog Peat's carrot grow log. It's a fun topic on its own...
Tue, 2009/01/13 - 6:13pm
#27
Week 5
Another week, a little more growth. The carrots have been thinned out, the removed ones were planted in another pot of perlite/vermiculite.
The bonus with growing with per & ver is that the seedlings are easily removed from the mixture, no messy soil clinging to the roots; a nice clean plant which is easily transplanted. The pot is still sharing the light with the cucumber plant, the cuke leaves are moved aside as and when they start to shade the carrots.
Sun, 2009/01/18 - 1:59am
#28
This is really cool Peat, I am looking forward to seeing how they turn out! Can I put in a request for a pict of a baby carrot if you thin them again? It's January, I have gardening cabin fever and would love to see some veggie life!
Sun, 2009/01/18 - 5:07am
#29
Certainly jewleeia, I will see how big they get in the pot first, and if I decide to thin then I'll put up a picture. 
They crop in 70 days so I'm looking at 10 weeks before I get them full size, it's 6 weeks tomorrow and they look quite small...
Tue, 2009/01/20 - 1:43pm
#30
Week 6
Another week, not a great lot happening on the surface - hopefully it's growing wild below!
I fed it some GH nutes, standard vegetative growth phase (EC of 1.6) to give the shoots a little helping hand.
Very cool! Have you actually done this?