Hydroponics FAQs – General Questions
What is Hydroponics?
Hydroponics is a method of growing vegetation in a nutrient rich water solution rather than soil. An inert growing medium that provides the root system good oxygen exchange, moisture retention, and drainage replaces soil allowing the root ball to direct access to its nutritional requirements. Rather than inefficiently accessing nutrients filtered through soil, the roots now have direct access to its nutritional requirements resulting in 30-50% greater yield and much faster growth rates than most other types of gardening methods.
Is Hydroponics easy?
There are a number of different hydroponics methods each with varying degrees of difficulty from very easy to more advanced. The ease of hydroponics also varies with the type of crop being grown. Smaller plants and vegetables are easier to grow than larger crops due to size and weight considerations. While leafy green plants and vegetables are much easier to grow than flowering or fruiting types of plants due to the amount of light power that is required for fruiting and flowering.
What are the different types of hydroponics systems?
There are six types of hydroponics systems but here are the most common three types you’ll generally see:
- Deep Water Culture (DWC) – DWC systems is one of the simpler and more efficient hydroponic systems and generally consist of net pots, a reservoir, and an air pump and air stone. Plants are suspended in net pots above a reservoir containing a nutrient solution aerated with an air stone. Roots hang down into the nutrient reservoir and continuously absorb the necessary elements to grow.
- Ebb and Flow (Flood and Drain) – The basic parts of an Ebb and Flow system are a reservoir, net pots, grow tray, water pump and a timer. In an Ebb and Flow system a timer triggers the water pump to flood a grow tray containing plants for about 10-15 mins. The nutrient solution then drains back down to the reservoir with the entire process repeating every hour or so depending on what type of crops are being grown and what type of grow media is used.
- Drip System – Very similar to DWC systems with the main difference being an active feeding mechanism rather than a passive one. Instead of simply allowing the root ball to search out and extend to the reservoir, a top drip system utilizes tubes to directly drip nutrient solution onto each individual plant.
Hydroponics FAQs – Nutrient Solution
How do you test and adjust pH?
The best way to measure your pH is to purchase a digital pH meter. These range from about $10 – $50 depending on how fancy you want to get. While these meters are extremely accurate they do need to be calibrated to ensure accurate readings. A low cost option is to use pH strips which are pretty foolproof and don’t require calibration. With whatever method you choose it is important to let your water sit for at least 12 hours in order for any chlorine present in your water to evaporate.
If your pH is above 6.5 or below 5.5 you can use a pH Up or pH Down solution to adjust accordingly.
Why is pH important?
Growing plants hydroponically requires a very specific pH range in order for optimal growth and nutrient absorption. If the pH of your nutrient solution is outside the required range your plants won’t get the necessary nutrients they need to grow.
How often should I check the pH?
It is quite normal for the pH of your nutrient solution to fluctuate on a daily basis. Checking and adjusting your pH level once every week or every couple of days should be more than enough.
How often should I change my nutrient solution?
Every week to two weeks is recommended. In between full changes you can top off your reservoir simply using pH balanced water. The more often you change your solution the better as this will ensure your plants are always getting the proper amount of nutrients and that your solution is at the proper pH. Another alternative is to wait until you’ve topped off 50% of your reservoir with pH balanced water.
Do I need an air stone?
Depending on what type of hydroponic system you are using you may not need one. In top drip and ebb and flow systems there is a continual circulation of water that will provide enough oxygenation and movement. You may want to consider adding one to a DWC system however as the nutrient reservoir is generally stagnant.
Hydroponics FAQs – Lighting
What is the difference between cheaper and more expensive grow lights?
More often than not the main difference between high end lights bulbs and cheaper ones is just the reflector. High end reflectors are designed to create more of a spread for both its light output and heat while budget reflectors typically don’t do as good of a job at dispersing light and heat.
How often should I change my bulbs?
For HID light bulbs (HPS and MH) most experts recommend changing light bulbs every 9-12 months. While the bulb may look like it still works fine your plants will notice a dramatic change in light output and your harvests will suffer as a result.
Hydroponics FAQs – Plant Health
The leaves of my plant are curling up!
If your leaves are curling up it may be a sign that your plants are trying to reduce their surface area in an attempt to retain water. Two possible problems may be either your lights are too close and are frying your tender plants or your fan my be blowing to strongly and drying out your plants. Try moving your lights a little further away and redirecting your fan so its not blowing directly at your plants.
The leaves of my plant are curling down!
If your leaves are curling down it may be a sign that your nutrient solution is too strong.
The lower leaves on my plant are turning brown!
If your plant is lit with a top light this may be an indication that not enough light is reaching the lower levels of your plant. This is quite normal and you shouldn’t be alarmed as the top leaves should capture enough light for your plant to continue to thrive. If you’d like you can provide supplemental light from the side to ensure your bottom leaves are getting enough light as well.