With the rising costs of fruits and vegetables, many have begun wondering how to urban garden, especially with the increasing uncertainty of the quality of our food, many in the pursuit to have the best health possible have decided to take matters into their own hands. To ensure they are getting the very best quality food for their families they have started an urban garden in their backyard. Even in big cities where space is very limited you can still grow quite a bit in an apartment, provided you have a window or grow lights that is.
There are hundreds of great ideas on urban gardening in your home, some better than others. Many methods require pots and dirt which can leave quite a mess if something bad happens, like a pet knocks a pot down or you over water and it flows out on the carpet.
Obviously growing outdoors if you can will provide you more flexibility in your design and scale ability but that is not the reality for many. Even if you have outdoor space available it may be unusable to you for many reasons such as lease restrictions. So that leaves you with one option if your serious about starting your own garden, (that’s right) take it indoors, but where’s the best place to start? I recommend you give aquaponics a try.
Why choose Aquaponics
Plants need Nitrogen, phosphorous, and Potassium to grow, that’s what the numbers on the fertilizer containers represent (10-15-10) is a good example. It is difficult to add organic matter to the soil after you’ve started your garden which is why you must add it before you plant as your mixing the soil, if you don’t have enough you have to supplement with a fertilizer.Most gardeners use fertilizer to feed their plants because it’s easier than trying to amend the soil after the fact or they don’t have the time to do it.
Aquaponics does the fertilizing naturally by using the processes of nature to create the fertilizer. Aquaponics is an ecosystem that’s created between fish and plants and once you get it going it is nearly self maintaining, minus a few additions of minerals like the phosphorous which is handled by the fish food you feed your fish and then your potassium which comes in many forms for the plants. All fish secrete ammonia from their gills and from their waste, the process that turns this into the nitrogen for plants to consume begins when the ammonia that is secreted by the fish (which is deadly to them in high enough concentrations) gets converted to nitrogen by nitrifying bacteria that lives in your growing media aka. Gravel.
Nitrifying bacteria is also in the soil of traditional gardens and is part of the nitrogen cycle, it turns the small amounts of ammonia that is produced by decaying organic matter like leaves, dead animals or their waste into nitrogen, plants then absorb it into their roots. In aquaponics however fish are extremely high ammonia producers and need constant filtration of their water to remove it, the plants absorb the converted nitrogen from the fish as their water is pumped through their growing media past the roots, you can think of the grow beds as a giant aquarium filter, clean water then returns to the fish tank thus finishing the filtration cycle.
If you have ever looked at an aquarium, the filter that hangs on the back that makes the little waterfall has a filter screen in it, this serves 2 purposes it catches large particulates to keep the water clear but more importantly provides a biological surface area or (BSA) for nitrifying bacteria to grow on. That brown slime you see on it is actually the bacteria colony and is doing all the work of keeping your fish healthy. It is also the same slime on the rocks that you slip on when trying to cross a creek bed and this bacteria will colonize down in the gravel of your grow beds, as the water flows through, it creates nitrogen.
This process happens naturally and is not dependent on anything you do, the bacteria travels in the air and colonizes anywhere their is ammonia, all you have to do is plant the plants and feed the fish for the most part, there are other things that you monitor and do on occasion but more on that later. In an aquarium tank however the nitrogen generally doesn’t get consumed unless you have plants in the tank and it will continue to concentrate forcing you to do a partial water change to lower the levels back to a safe range. In aquaponics however you will never have to change out the water as long as everything is operating right, you will occasionally have to top off the water due to evaporation.
The beauty of this style of urban gardening is that it’s clean, convenient, easy to maintain and you can grow a lot in a little space. Your plants will grow bigger and quicker than conventional dirt gardening. Since your growing in gravel, harvesting becomes a matter of simply pulling the whole plant out, roots and all effortlessly. You can grow your plants closer together since there is virtually no competition for nutrients since they are being fed constantly. You can scale your garden as big or small as you’d like. With the exception of a little water evaporation it is also zero waste, traditional garden watering wastes the majority of the water used on it since it drains away or evaporates.
If you already own a fresh water aquarium a grow bed would be a perfect addition and would eliminate costly filters and provide a return on your investment.
Choosing a Location
Choosing a location is a pretty straight forward process. We all know plants need sunlight to grow so you ideally want a spot in front of a window that receives sunlight for most of the day. You also want to have as much room as you can reasonably spare to be the most productive and be out of the way of traffic if possible. If you don’t have a window or the only room you have is a closet you can still start your garden but you will have to provide the sun through artificial lighting. If all you have is a kitchen window you can still grow a couple heads of lettuce or some herbs.
Design your System
Your system design is going to be dictated by your location that you settle on. You will need a shelving rack to make the most of the space in front of a window or in a closet. You will need to settle on what you want to grow before you begin because it will affect your shelf spacing and positioning of your crops. If you are going to grow anything tall you will want it on top and things like lettuce that get harvested at about a foot are perfect for middle shelves. There are several design methods but the simplest one is bell siphon grow beds. Instructable coming soon. You can also do deep water culture (DWC) where instead of gravel you have a filter that the bacteria grows on and the plants sit in net pots and are placed in holes on a styrofoam sheet that floats on top of the water in your trays, this method is particularly good if you really only plan on growing some salad vegetables and herbs. Instructable coming soon.
What to Grow
You can grow nearly anything in an aquaponics system. It’s really only limited by your growing medias ability to support the plant and the amount of room you have, so you obviously wouldn’t plant watermelons because the vines would be in the middle of your living room. In reality your lighting restrictions if any, will ultimately determine what you can grow. If you don’t have enough light some plants won’t grow well, this is particularly true of fruiting plants. Leafy vegetables like lettuce don’t require much sun light, they can be grown 4-6 inches apart, they also grow quickly so these make excellent choices for indoor growing where the temperature is regulated because lettuce doesn’t like the heat of summer. Chives and other herbs do very well as well.
Another reason why fruiting plants are a bad choice for indoors is because most of them need pollination and they simply won’t get that indoors. You can do things like take a q-tip and prod around the flowers yourself or point a fan at the plants in the hopes that it will knock some pollen loose. Strawberries in particular are hard to do this with because the size of the berry is dictated by how well it’s pollinated, bees and other insects are really the only effective pollinators for them. Tomatoes are easy to pollinate but the plants have a strong odor so it may not be a good choice to grow if your area is particularly small.
Making the most of your Space
When planting your crops you will want to consider how often you want to eat that food. For instance if you just want to plant and harvest in bulk you would fill all your beds at once, but if you want a steady supply week after week then you will need to apply the practice of crop rotation. This would involve you looking at your seed packet and determine the number of days from planting to harvest. So if a head of lettuce takes 30 days then you would divide the space that you have allotted for that crop by 4.
So for example you have your grow beds set up and have calculated that at 6 inches apart you can grow 12 heads of lettuce, so you would plant 3 heads the first week, exactly 1 week later you would plant another 3 and so on until you get to the 4th week then you would harvest your first 3 you planted and plant 3 more in their place and do that each and every week as long as you want thus creating a sustainability.
Now that we’ve considered some of the basic details on how to urban garden using aquaponics we will go in to more depth of the steps involved to build and maintain a system including keeping your plants and fish happy and healthy.