Why Nutrition is Key in Hydroponics
Hydroponics is a method of growing plants without soil. Instead, the plant’s roots are suspended in a nutrient-rich water solution. There are a few key things to understand about hydroponics:
- Plants are grown in containers like buckets or pipes, not ground soil.
- The nutrient solution delivers food and water directly to the roots.
- Special hydroponic systems pump and re-circulate the solution.
There is no soil, therefore, the plants require nutrients from you. That’s why getting the right nutrition is crucial in hydroponics:
- Plants need the right amounts of nutrients to grow properly. Too much or too little will cause issues.
- The main nutrients plants need are nitrogen, phosphorus, and potassium (NPK).
- Plants also need other micronutrients in smaller amounts like calcium, magnesium, and iron.
- You must carefully mix the right formula and maintain it in the hydroponic system.
- Nutrient levels and pH need regular monitoring and adjustment.
- Without proper hydroponic nutrition, plants will be stressed and have problems.
While soil gardening relies on nutrient-rich soil, in hydroponics the nutrients have to be manually provided and balanced. By getting the “recipe” right, your hydroponically grown plants can thrive!
Diving Deeper into Hydroponic Nutrients
Earlier we discussed the three main macronutrients plants need: nitrogen (N), phosphorus (P), and potassium (K). Let’s explore these and other nutrients further:
Main Macronutrients
- Nitrogen (N) – Supports healthy green growth and plant proteins. Deficiency causes yellowing leaves.
- Phosphorus (P) – Important for root, flower, and fruit development. Boosts buds and blooms.
- Potassium (K) – Crucial for overall plant health. Helps regulate water uptake.
Important Micronutrients
- Calcium – Strengthens cell walls. Prevents blossom end rot in tomatoes.
- Magnesium – Key for chlorophyll production and photosynthesis. Keeps leaves green.
- Iron – Facilitates energy production. Prevents yellowing between leaf veins.
- Manganese – Involved in nutrient breakdown and absorption. Needed for new growth.
- Zinc – Plays a role in enzyme and hormone function. Deficiency stunts plants.
Getting the balance right is key
- Too much of any nutrient can “burn” plants or cause toxicity.
- Deficiencies create obvious symptoms like discolored or twisted leaves.
- Ensure a balanced blend of macro and micronutrients suited for each growth phase.
- Adjust levels based on plant signals to prevent excesses or deficiencies.
With the ideal nutrient balance, your hydroponic plants will thrive from seed to harvest!
Choosing the Right Hydroponic Nutrients
When starting hydroponics, one key decision is whether to use organic or synthetic nutrient solutions. Here’s an overview of the pros and cons of each:
Organic Nutrients
Pros:
- Derived from natural sources like fish emulsion, kelp, and compost teas
- Enhance soil microbial life
- Leave no chemical residue
Cons:
- More expensive
- Spoil faster than synthetic nutrients
- Require more frequent application
Examples: General Organics, Earth Juice, Dr. Earth
Synthetic Nutrients
Pros:
- Concentrated formulas are more affordable
- Extended shelf life compared to organic
- Customizable blends with precise NPK ratios
Cons:
- Made from chemical salts
- Must be used carefully to avoid buildup
- Not permitted in certified organic gardening
Examples: General Hydroponics Flora Series, Advanced Nutrients, Botanicare
When first starting out, a reputable all-in-one synthetic blend is usually the simplest option. As you gain experience, you may wish to explore making your own custom organic or synthetic nutrient solutions.
The key is choosing a complete, balanced product suited to your plants’ needs and your hydroponic system.
Step-by-Step Guide to Feeding Your Hydroponic Plants
Once you have your nutrients, it’s time to master the process of properly feeding your hydroponic system. Follow this step-by-step guide:
Carefully Mix Nutrients
- Start with a reputable brand of synthetic or organic hydroponic nutrients.
- Check the label for mixing instructions specific to the product.
- Measure out the required amounts of each nutrient part (A, B, micros, etc).
- Mix the products together in your reservoir, using warm water to dissolve.
- Double check EC/TDS and pH levels match target ranges.
Transfer Nutrient Solution to Reservoir
- Run solution through tubing and components to flush before adding plants.
- Make sure all pumps are working to circulate the nutrients.
- Place plants into the system containers and fill the reservoir.
Maintain Proper Conditions
- Use an EC meter to track electrical conductivity/mineral levels.
- Monitor pH regularly with a pH meter, keeping within 5.5-6.5 range.
- Top off the reservoir with plain or pH-adjusted water as needed.
- Completely replace nutrients every 1-2 weeks.
Adjust Based on Plant Needs
- If leaves are yellow, increase EC/nutrients.
- If tips burn, decrease EC levels.
- Leach systems periodically to prevent salt buildup.
- Supplement key nutrients if deficiencies appear.
- Reduce strength for seedlings and young plants.
Common Feeding Mistakes and How to Avoid Them
Here are some common issues and how to avoid them:
Overfeeding
- What does it look like? Leaf tips and margins turn brown or yellow, roots show damage
- How I fixed it: Reduced overall nutrient levels and flushed the system to remove excess
Underfeeding
- What does it look like? Slow and stunted growth, leaves yellowing or dropping
- How I fixed it: Slowly increased nutrient concentration until plants improved
pH Fluctuations
- What does it look like? Nutrient deficiencies even at proper levels
- How I fixed it: Monitored and adjusted pH regularly to maintain the 5.5-6.5 range.
The key is close observation and quick correction.
Some tips
- Start nutrients lower than recommended, increasing slowly.
- Check pH and EC/TDS levels frequently to catch issues early.
- Flush systems to correct excesses and clear out salt buildup.
- Leach soilless media regularly to avoid nutrient accumulation.
With vigilant monitoring and readiness to adjust, you can avoid common hydroponic feeding pitfalls. Let your plants guide you to the right balance!
FAQs on Nourishing Hydroponic Gardens
If you’re new to hydroponic nutrition, there are probably some lingering questions. Here are answers to some frequently asked questions:
Q: How often should nutrient solutions be replaced?
A. Every 1-2 weeks, more often for faster-growing plants.
Q: Can I use compost tea instead of commercial nutrients?
A: Compost tea doesn’t provide all the nutrients plants need but can supplement.
Q: Is tap water ok for the reservoir?
A: Tap water must be left out to dechlorinate but may raise pH and EC levels.
Q: Why do leaf tips burn even though I follow mixing directions?
A: This often occurs from accumulated salts. Try flushing the system.
Q: How can I provide micronutrients lacking in my base nutrients?
A: Add a micronutrient supplement or foliar spray targeted to the specific need.
Q: Is there a general rule for EC/PPM levels?
A: 500-800 PPM is a common target, increasing with plant maturity.
Q: How much pH fluctuation is acceptable?
A: Fluctuate no more than 0.2-0.3 up or down to maintain nutrient availability.
Bertha M. Molina
https://www.hydrogreenspace.com/how-to-feed-hydroponic-plants/