This week I promised you we would talk about aquaponics.  So today, let's discuss types of aquaponic systems:

The first type of system, the Nutrient Film system, is adopted from the hydroponics community.  In large commercial systems, water and nutrients are constantly pumped through PVC tubes.  Plants rest in holes drilled along the top of the PVC tubes.  This system requires a separate filtration tank to remove fish solids from the water before the water reaches the growing plant roots.   If the solids are not removed,  they begin to build up on plant roots, blocking nutrient absorption.  Separation and treatment of these solids requires space, time and energy.

Another system called the deep water raft system is also very similar to standard hydroponics grow systems.  In this system, however, plants are set in netted pots (like the ones you buy for your garden ponds) on a foam raft which floats over a water tank.  This system can be built at home over an existing aquarium, provided the fish are more carnivorous than herbivorous.  Goldfish love plants, so I’m thinking tiger barbs, catfish, cyclids and maybe some of the tetras and gouramis would be nice for this project.  Maybe you could just add your extra minnows from your latest crappie fishing jaunt.  You should also add an extra air pump and air stone to provide the plants with more oxygen.  This is the system I will attempt to build in my 3 gallon aquarium.  I plan to use it to start seedlings for my larger aquaponic system. 

My larger system will be a basic flood and drain system, specifically the Chop II system by Murray Hallam of Practical Aquaponics in Australia.  This is the third type of aquaponic system.  If you’ve grow sprouts, you’ve done a flood and drain system in its simplest form.  In this system, Unlike the previous two systems, plant beds are filled with growing media instead of water only.  The growing media acts as a biological filter, which is basically a place for bacteria to grow.  This bacteria is going to break down the fish waste (ammonia) into nitrites. Then another, slower growing bacteria converts the nitrites down into nitrates…and guess what? Nitrate is a form of nitrogen plants can use.  Because this process takes place in the grow beds, no extra filtration is needed.  ¾” gravel or hollow clay beads called hydroton fill the grow beds.  Other materials can be used but they may alter the chemistry of the water and cause pH problems later on. Flood and drain systems can grow a wider variety of plants because the roots are exposed to more oxygen.  Water flows into the grow beds, reaches a set level, then flows back out again.  There are many different version of how to get the water from tank to tank and back again and many more will be developed as this potentially world altering food technology evolves.

Here’s where my systems sit:

This week I ordered two more 50 gallon stock tanks and bought another 300 liters of hydroton. I also ordered all my garden seeds for the season and started bok choy, onions, spinach and lettuce seed in my biodome.  Spinach and bok choy are already sprouting inside, daffodils and forsythia are starting to bloom outside.  What’s happening in your gardening world? 

Starting your own seedlings is fun and easy.  This year I will have two gardens, my container garden and aquaponics system here and a co-op garden with a friend who lives down the road, so I’ll need more plants than usual.  I’d also like to sell a few seedlings here at the local farmers market, so I’ll be growing quite a few different seedlings this year…things you won’t find at the local big box stores.  I spent a good deal of the morning shopping for these items at a new seed store:  www.botanicalinterests.com.

They offer a very nice selection of heirloom plants in small quantities, ideal for the container gardener! For more great seed catalogs, check out the February Edition of Carolina Gardener magazine. 

Back to planting, I can’t plant the seeds I mail ordered today.  Even if I had them I wouldn’t be planting them today.  Typically here in the Midlands we don’t want to put summer transplants out until April 1^stin our container gardens and about two weeks after that for our in-the-ground gardens, so I’ll be planting more spinach, lettuce, onions and maybe a few snow peas to replace the ones knocked down by the cold winds we’ve been having.  I must say the winds have done horrible things to my normally most sheltered spot:

The peas are not as bad they look though…most of the plant is just hiding behind the container where the wind blew it down…I do need to pollinate the pretty blossoms.  Not many pollinators out there in this cold wind.

But back to the seedling starts:

First, sterilize the seed starting trays with a solution of bleach or vinegar and water.  I just put a splash of bleach or a cup of vinegar in my mud sink, fill with water to cover the trays and let things sit a bit.  VERY excited about my find at the Master Gardeners sale last year…I have a slightly used bio dome seed starter this year.  It has a taller lid than most seed starting kits and a vent you can use to regulate humidity levels.  

I bought sterile planting media instead of the bio sponge refills, which is another reason to start early to try things out. What I didn’t notice until I started cleaning the bio dome is that the foam insert has holes all the way through the foam, so the soil goes in and comes right back out…oops!  If you don’t follow directions exactly, you can’t expect exact results, right?  The planting media I bought doesn’t hold together like the bio sponges, so instead of putting my planting media in a bucket and covering it with just enough water to make it evenly moist, I will be putting the planting media into the foam insert and watering it well in there. All of this can be done while the seed starting trays are being sterilized.

Once your trays are filled with planting media, add your seeds (don’t forget to label them as you go…you will NOT remember what they are, at least I never do and a surprising number of seedlings look quite alike!).  You can put the spinach, onion and lettuce seeds on top of the unplanted holes and pat them down into the soil.  Sprinkle a little dirt over the onion and spinach seeds but leave the lettuce seeds uncovered. 

Now, just a word about onions: here in South Carolina, you should not plant onion seeds at any time other than fall; so I’m just experimenting a bit.  I want bunching onions, so I’m planting bunching onions, which technically should grow anytime.  We’ll see, won’t we?  Another word on onions: they can be short-day, long-day or day neutral.  Long-day varieties will not grow here in the south.  According to Clemson, my onions are going to bolt as soon as the weather turns warm, but I’ll probably be chopping them up for omelets way before then!  Happy Planting!

So, I was going to cook beets this week…I harvested them and guess what?  I was ROBBED, that’s right, ROBBED…see what happens when you DON’T give a dog a bone, as the song says you should?  But she’s so cute, who can be angry for long? 

Actually, this is a game we’ve played for years.  I don’t like feeding my dog rawhides or other questionable chew toys, so we started playing in the garden when she was a pup.  I would pull up carrots and other root vegetables for her to eat (in the yard…really fresh carrots and beets stain anything they touch!), while I worked, but her favorite plant is the asparagus plant, as you can see.

She also likes to attack empty flower pots, so she enjoys spring planting very much and waits at my side to steal any pot as soon as I empty it.  Of course, the game is no fun if I don’t go chase her, at least not as MUCH fun!  Here’s a link to the beet game we played this past weekend: 

So having failed to rescue my beets, let’s talk about the New Year and what’s coming up:  my new goal is to publish here weekly.  Every other week I will focus on garden to-dos and fun family ideas.  On the alternate weeks, aquaponics will be the focus. 

Aquaponics is the combination of aquaculture and hydroponics.  You see, this goes back the sustainability we discussed last post.  Hydroponics require expensive chemicals and fairly frequent water changes.  Aquaculture produces fish waste which requires treatment and disposal.  Aquaponics combines the two, using the excess fish waste to feed the plants which in turn filter the fish water, cleaning it.  And anyone can do this at home, at least that’s what I’m out to prove this year.

 I will have two systems going.  The first will be a fairly large system requiring some outdoor space, using a 250 gallon IBC tote and several 50 gallon stock tanks.  This system will use the ebb and flow method.  My second system will be a 3 gallon aquarium with a floating raft on top.  This weekend, I bought hydroton pebbles and one stock tank for my large system and started making a list of other items I will need. Hydroton is expanded clay beads used in hydroponics as growing media.  You can use ¾” gravel in your aquaponics system, but hydroton weighs about 1/3 as much as gravel.

Here’s where my garden is right now:  my mini green house has been put together and sits outside full of tropical and tender perennials like my lemon tree, stevia plant, lemon grass, basil and a volunteer tomato I found growing in my mustard plants.  One of my blueberries, being very confused by recent weather, blossoms as we speak, as do my snow peas, so I’ll be pollinating this week. Spinach is sprouting, and I need to plant more lettuce, which I will do this week, for next week’s blog, showing you how to start seeds inside.  Until then, have a great week!

If you’d like, you can find me on Facebook: Sharon Self Johnson, linkedin (sccontainergarden@gmail.com), youtube or Google+ (if I ever figure it out!).

Remember, bloom where you’re planted!