Ask the Hydroponic Gardener

In My Humble Opinion
1

My landlord and I have been growing conventional gardens in our backyards for a couple years now. This year, our gardens didn’t do so well, and landlord started pondering hydroponics, knowing I had done some of that with my dad 30-35 years ago.

This month we decided to go ahead and we’ve set up a hydroponic rig in the apartment above mine, which is vacant and will need considerable work before it can be rented out, but is in good enough shape for the project.

Specifically, we’re using ebb and flow techniques. Our first plants sprouted as of last night, so we’re under way.

Anyone else who has done hydroponics at any level or with any technique is welcome to contribute, answer questions, etc.

So… questions?

2

What are you using for light? What are you growing?

3

Well, we are NOT growing anything illegal, let me get that straight! Yes, that seems to be a common real life question.

At present, we are growing radishes (they are currently the ones showing sprouts) and spinach. We are starting with just a few plants to make sure we have our system working properly before investing time and effort into a lot of plants. Next up on the list is chard, a favorite of both of us and difficult to find in local stores. After that, we might move on to bell peppers (expensive in stores around here) and tomatoes (I don’t eat them, but I’m told fresh, homegrown tomatoes are always superior to store bought). Much depends on our current success.

We’re currently using 2 grow light bulbs supplemented by natural sunlight coming in the south-facing window of the room we are using for the project.

I should probably state now that we are NOT using the most advanced, sophisticated, and scientific of set ups. I’m sure there are better and more efficient ways to do this, however, we are working on a tight budget to grow some fresh supplemental vegetables using mostly materials on hand or low-cost supplies. Hydroponic enthusiasts can go on and on and on about optimizing lights for growing plants. In our case, we’re making sure they have least 14 hours a day of light, and the natural sunlight will, we hope, make up any deficiency posed by the artificial lighting.

(In an experiment last year I empirically determined that that apartment did NOT receive sufficient natural light late November through early February to sustain plant growth, although from March onwards it does, Thus, the use of artificial grow lights.)

4

What sort of set up are you using? I’ve seen some instructions for using rubbermaid storage containers and 2 liter soda bottles and an aquarium pump I’ve been wanting to try.

5

That’s sort of what we’re using, actually…

We’re using a plastic tub/tray filled with pea gravel for a substrate, a 20 gallon bucket, and a pump with a float switch.

When I did it with my dad we used sanitized gallon milk jugs to hold the nutrient fluid (or “hydro juice” as some call it), connected to the tub via tubing. We’d physically lift the jugs above the plants to flood the trays, then lower the jugs below the trays to drain them. That had to be done several times a day.

This time around, as mentioned, we’re using a pump and a timer. The bucket reservoir sits under the tray. The timer turns on the pump twice a day. The pump does it’s thing until the float switch gets low enough, at which point it turns off the pump. The tray drains back into the reservoir bucket via gravity power, ready for next time. We spent a day or so working out the time on everything before planting.

Just be careful selecting materials, as you don’t want nasty stuff leaching into the fluids or the plants if you plan on eating them.

6

Since the OP wishes to share experiences, this is better suited to IMHO than GQ.

Colibri
General Questions Moderator

7

I’ve thought about hydroponics before. What’s always stopped me is that it seems like a lot of trouble to keep the appropriate nutrients for the plants. To that end, I’m pondering a small aquaponics rig, so that the fish provide the nutrients.

What are you using for your nutrient solution? And how much upkeep does it take?

8

If you don’t mind spending the money there are now a multitude of nutrient mixes for plants. In fact, there are even mixes specific to particular plants such as tomatoes. That is the easiest way to do this, buy something already formulated and balanced.

However, we do mind spending the money. Although it is not recommended by the hydroponics fanatics, we started with commercial plant fertilizer of the “Miracle-Gro” and similar brand varieties. One of the problems of these fertilizers is that they tend to have too much nitrogen, which can burn the plants when too concentrated. They can also have their nitrogen in a form that plants can’t utilize without soil bacteria which is, obviously, lacking in soilless growing conditions. On top of that, they also commonly lack things like calcium and sufficient iron. So we bought two different brands, which complement each other’s lacks when mixed 50/50, contain usable nitrogen, and our well water just happens to be mineral rich in iron, calcium, and several other minerals.

Yeah, OK, that IS a bit involved. And despite the nay-sayers, this did work for dad and me 30 years ago. I will say, however, that it works best for leaf crops rather than those that are fruiting types. Since we’re largely growing spinach that shouldn’t be a problem. Again, it’s not the optimum solution for optimum results, but once you get the mix figured out it’s relatively easy.

There are also numerous recipes on the internet for mixing your own nutrient solutions in large quantities.

Right now we’re estimating changing the nutrient out every two weeks. However, you do need to keep an eye on things, the fluid level and the plants. After three days, for example, we had to add another gallon to our current 12 gallon reservoir because of evaporation. So you need to keep track of these things until you find out the rhythms of your system and needed maintenance. Once it’s up and running you can, with timers and pumps, leave it unattended for days at a time so it’s not a constant preoccupation.

So, right now, I’m checking it once a day, usually the night flooding so I can check pumping, fluid levels, and drainage. If it continues as it currently is then it looks like checking in twice a week, with a fluid change out every couple weeks, should be sufficient.

The thing is, there isn’t just one way to do things. If you are contemplating adding fish to the system you’ll still need to provide maintenance. I’ve never tried that approach before, so I don’t know how much complexity that might add to the system.

9

I wasn’t really thinking the the fish would eliminate maintenance. I just don’t want to turn into one of those folks carefully measuring out every nutrient solution to get the perfect mix. I do enough of that at work! (I work in a research lab.) My understanding is that with aquaponics the only nutrient input is fish food. The fish convert it to plant-useable nutrients in the water.

I’d love to try it on a scale that would allow eating-size fish, but that’s a lot of money. I was thinking of rigging up a system with a small-ish tank of freshwater aquarium fish feeding an herb garden. Not too big to live in the house and I’ve heard that herbs do well in hydroponic systems. Do you have any experience with herbs in your hydroponic system?

10

Never heard of that, but I suppose you could work such a system out. But for regular hydroponics you don’t really need EXACT measurements - there’s some leeway there. If you think about it, out in the world of dirt based plants, none of those plants has precisely exact nutrition and perfect conditions. Plants have some flexibility, you know, they have to.

So I’ll freely admit we’ve never used an exact mix, just an approximation, and when I’m mixing it I’m not using exact measures. Close is good enough.

Well, you need to start small to work out your system and get some experience. Back when dad and I were doing it we got parsley, basil, and maybe a few others to grow. I remember the parsley coming up in half the usual germination time. The problem with herbs is that if the light isn’t sufficient they’ll get “leggy”. But that’s true of any plant to one degree or another. Herbs do work well with hydroponics.

The Aerogarden is a commercially available “airponics” growing system, a type of hydroponics, that includes herb seed kits. However, at $100 each, plus pricey replacement supplies, it’s pretty expensive. Our entire set up, which is potentially just as productive if not more so, cost 1/3 of that and we’re not dependent on that company to supply new seeds, replacement light bulbs, etc. There was a thread on aerogardens here on the Dope back in August. It’s one way to get a taste of hydroponics with a ready to go set up that doesn’t require you to do research yourself.

For a system using fish to provide nutrients I’d advise doing some research first, or trying a more conventional set up first, but hey, if you want to go for it do it.

11

Why hydroponics and not just grow lights and plants in soil? I’ve recently bought a couple of grow lights, one for starting seedlings and one for more mature potted plants that I want to bring in when it gets cold, that we have used like you in a south facing window. The grow lights are pricey and take some getting used to. Hydroponics seems like another level of learning.

How long will such a system last before you need to tear it down and restart? I’ve seen systems in a hydroponics store and they look like they get pretty crusty after a while.

12

Because our do it yourself rig is actually cheaper than buying potting soil in sufficient quantities and rigging up an automatic watering system. That’s one advantage to DIY over buying a ready to go rig.

We also put it together with future cleaning in mind. Everything disassembles for a thorough cleaning. Cleaning should be done after you harvest a crop, but with a proper set up and care nothing should be getting “crusty”.

13

While vacationing in the Caribbean on the island of Saba, I noticed many hydroponics gardens. The island is a very steep extinct volcano, and all the flat land is occupied by homes, roads or businesses. Since there is almost no room left for a garden, many back porch roofs or garage roofs are covered with hydroponics veggie gardens. With almost all of their food imported to the island, any fresh veggies are in huge demand.

14

I keep seeing this thread and thinking it says “Ask the hypochondriac gardener.” I’d ask if constantly thinking you were sick had any effect on your plants.

How much space does your get up take? I’d love to do something hydroponic, inside, year round… but I’m concerned about having the space.

15

Well, the size of your set up can vary considerably. We have started with a system that’s approximately 4 feet tall, about 3 feet by 2 feet otherwise. The tray with the plants sits on a table (actually, a plank across to sawhorses) with the grow lights suspended above, and the fluid reservoir beneath.

You certainly could make a smaller rig. Potentially something as small as 1 x 1 x 3 feet maybe.

There are commercial hydroponics planters that are smaller than that, but they do come with a higher price tag.

We plan to expand in a couple weeks, assuming nothing goes amiss.