Hydroponic gardening continues to grow in popularity with the urban gardening movement. Not everyone has access to a community garden plot or a patio to grow a container garden. Hydroponics (growing indoors and in water) create a perfectly accessible option for everyone. Some folks may be intimidated by the idea, believing that too much complicated science goes into the process. However, the Kratky method cuts away any complications and makes the plant do all of the work for you. This simple system requires no air pumps, no electricity, and minimal attention. In this introduction to the Kratky method, I hope you are inspired to try growing an indoor hydroponic garden.
Let's get started.
The nature of the hydroponic system requires a deep growing vessel for the plants. As time goes on, the plant's need for water will add extra space in the container where the roots will receive oxygen. Areal roots will form as other roots will grow further down in the container towards the water. This system's nature means you will need to find a container that is the appropriate size for the variety you are planting. The tomato plants have been placed in a 5-gallon bucket in the image above to ensure they have ample space to grow. Alternatively, large storage containers can be transformed into hydroponics planters. Smaller rooted varieties like lettuce will not need as much space.
Disclaimer: Some plastic is not recommended to plant in because the chemicals can cause issues for the harvest. Plastics polyvinyl chloride (PVC) (recycling #3, polystyrene (recycling #6), and polycarbonate (recycling #7) are all considered dangerous to plant in because of their chemical makeup. Look for food-grade plastics to plant in. To read more on what plastic is best to grow in, click here.
The growing solution is the defining characteristic of hydroponic gardening. Instead of soil, a vitamin-rich water mixture is built up with fertilizers rich in everything the plant will need to thrive. There are two main steps to this process. The first is to make sure your water (city, well, or otherwise) has the perfect ph level. Leave any water you plan to use in a container overnight to allow it to distill and evaporate any excessive chemicals. There are ph balancing solutions you can add after your nutrients if the ph becomes too high or too low. Secondly, You need to add nitrogen, calcium, and plant fertilizer to your mix. Calcium nitrate takes care of the calcium and nitrogen needs, and you can use a standard master blend mixture for the fertilizer option. Additionally, Epsom salts aid the permeability of the other ingredients.
Mix a ratio of 1:1: .5 into the water mixture and mix until completely dissolved. For a 5 gallon bucket, for example, add 2 tablespoons of calcium nitrate, 2 tablespoons of master blend mix, and 1 tablespoon of Epsom salt to add the desired amount of nutrients. Depending on the size of your container, multiply or divide to the desired amount.
Net pots are essential for all hydroponic setups because they allow the roots to access the water and oxygen they need. Find net pots that will fit the varieties you want to grow. For beginners, two-inch net pots are a great place to start. For the easiest access, these are a very affordable option! You might be wondering at this point; "What about root rot?" After setting the roots near the water source, time will actually take care of this issue. The plant will grow and need nutrients, which it will pull from the water. As a result, the water level will go down. Slowly receding water levels will make the plant create aerial roots, roots that will bring oxygen to the plant, as longer roots grow farther to continue with water uptake.
Lastly, seeds for a hydroponic setup need to be started before being placed in net pots. Start seeds in Rockwool material instead of the soil mixture. Once sprouted, place the seedlings into net pots. Secondly, you will need material to hold the seedlings in place. Clay pebbles or excess Rockwool are the perfect material for keeping seedlings in place. Some have even suggested using pool noodles as a much cheaper alternative to rock wool. However, we recommend doing your own research to know if pool noodles are made of garden safe materials.
– Kaitlynn from MIgardener