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The Second Reason Tower Gardens Struggle

Healthy plants start with proper nutrition.

Whether you're growing leafy greens, herbs, strawberries, or tomatoes, understanding how nutrients work and adding the correct amount in your Tower Garden is one of the biggest keys to faster growth, healthier roots, and better harvests.

In this Guide You'll Find...

Quick Start Nutrient Tips

  • Mix nutrients into water separately before combining
  • Keep pH between 5.5–6.5
  • Use half strength nutrients during very hot weather
  • Top off water regularly
  • Fully replace reservoir water every one to two months
  • Watch plants daily for signs of stress
Tower Garden FLEX Outdoors

What Do Nutrients Do?

In traditional gardening, plants get nutrients from soil.

In a Tower Garden, the water delivers nutrients directly to the roots instead.

These nutrients provide the essential minerals plants need for:

  • Leaf growth
  • Root development
  • Flowering
  • Fruit production
  • Overall plant health

Without proper nutrients, plants may:

  • Grow slowly
  • Turn yellow
  • Wilt
  • Develop weak roots
  • Produce smaller harvests
Tower Gardne HOME with LED Lights

How Tower Garden Nutrients Work

Tower Garden nutrients are designed specifically for plant and human health.

The nutrients dissolve into the water reservoir and circulate through the tower, delivering minerals directly to plant roots.

This allows plants to:

  • Grow faster
  • Use nutrients more efficiently
  • Produce larger harvests
  • Avoid many soil-related issues

Because the nutrients are delivered directly to the roots, maintaining the correct balance is important.

Too little can slow growth. Too much can stress plants or cause nutrient lock.

How Often Should You Add Nutrients?

  • Nutrients are added when refreshing or replacing reservoir water
  • Water should be topped up regularly as plants consume it, especially when temperatures are near freezing or above 90 F
  • Reservoirs should periodically be emptied and refilled

Large fruit-producing crops like tomatoes, cucumbers, peppers, and melons use more water than leafy greens and herbs, so you'll typically need to check and top up the reservoir more frequently when growing these crops and during hot summer months.


Not sure how much nutrient to add or when?
👉 Read our full guide on how much and how often to add nutrients →

How to Mix Nutrients Correctly

Step 1: Fill the Reservoir with Water

Never use softened water, and filter city water to remove chlorine/chloramine. Your plants will thank you!

You can learn more about water quality in our Water Guide.

Step 2: Add Nutrients Separately

Always add the A and B liquids separately into the water.

Do not mix concentrated nutrients together before adding them to the reservoir.

This helps prevent nutrients from binding together before dissolving properly.

Step 3: Mix Thoroughly

Allow the nutrients to circulate fully before testing pH.

Understanding pH

pH affects how easily plants can absorb nutrients.

Even if nutrients are present in the water, plants may struggle to absorb them if the pH is outside the ideal range.

Recommended pH Range

Most Tower Garden crops perform best between:

5.5–6.5 pH

Within this range, plants can absorb nutrients more efficiently.

Signs of pH Problems

Improper pH may contribute to:

  • Yellow leaves
  • Brown spots
  • Slow growth
  • Curling leaves

If plants suddenly begin struggling despite proper lighting and nutrients, pH may be worth checking.

EC & TDS Explained

EC (Electrical Conductivity) and TDS (Total Dissolved Solids) meters help estimate the amount of dissolved minerals in the reservoir.

These tools can help growers:

  • Monitor nutrient strength
  • Detect large changes in the reservoir
  • Avoid overfeeding

However, numbers alone do not tell the full story.

Even if EC or TDS readings appear normal a reservoir can still have:

  • Nutrient imbalances
  • pH problems
  • Poor water quality
  • Nutrient lock

👉 Want to understand what nutrient lock is and how to fix it?
Read our guide to nutrient lock →

For many home growers, visual plant health is often the most useful indicator.

Seasonal Nutrient Adjustments

Summer Growing

  • Plants may drink more water and they don't require more nutrients
  • Reservoir temperatures rise and water can evaporate
  • Nutrient concentrations can build up

During summer, reduce nutrient strength to help avoid plant stress.

Cooler Weather

  • Growth slows
  • Water usage decreases

Nutrients can be added at the regular strength

👉 Take a deeper dive into Adding Nutrients in the Summer Months →

Strawberries Growing in Tower Garden

Signs of Nutrient Problems

Possible Underfeeding

  • Pale leaves
  • Slow growth
  • Weak plants
  • Smaller harvests

Possible Overfeeding

  • Leaf burn
  • Brown leaf edges
  • Curling leaves
  • Stunted growth

Sometimes, adding more nutrients actually makes plants worse, especially when the issue isn’t nutrients at all.


👉 Not sure what your plants are telling you? Visit our Tower Garden Troubleshooting Guide to diagnose common problems →

What Is Nutrient Lock?

Nutrient lock occurs when plants are unable to properly absorb nutrients, even when nutrients are present in the water.

This can happen because of:

  • Excess nutrient buildup
  • Salt accumulation
  • Imbalanced minerals

Nutrient lock can mimic nutrient deficiencies. Common symptoms include:

  • Yellowing leaves
  • Burnt tips
  • Slow growth

If nutrient lock is suspected:

  • Refresh the reservoir

👉 Want a deeper breakdown of what causes nutrient lock and exactly how to fix it?
Read our complete nutrient lock guide →

Common Nutrient Mistakes

Overfeeding

More nutrients does not mean faster growth.

Ignoring Water Quality

Poor water can block nutrient uptake.

Forgetting Seasonal Changes

Summer = different behavior.

Not Monitoring Plants

Your plants will tell you what’s wrong.

Related Guides & Resources

❌ Not Getting Enough Direct Sunlight (Outdoor Growing)

This is the #1 issue we see.

A Tower Garden might look like it’s in a bright spot, but if it’s not getting at least 5 hours of direct sunlight (ideally closer to 8+ for fruiting plants), growth will suffer.

Common signs:

  • Slow growth
  • Small leaves
  • Leggy, stretched plants
  • Pale, washed out colored leaves

👉 What to do:
Make sure your Tower is placed where it gets true, direct sun. Watch how the sun moves throughout the day. Even partial shade from a fence, house, or nearby plants can make a big difference. If you wouldn't get a sun tan in that location, it's not enough.

❌ Using a Shade Cloth When It’s Not Needed

We see this a lot, especially in Florida.

While shade cloth can be helpful in extreme heat, it often reduces light more than people realize and can actually slow plant growth.

In most cases, it’s not needed — even in summer.

👉 What to do:
Remove shade cloth and monitor your plants. In our experience growing in both Central and South Florida, Towers perform better with full sun than with reduced light.

❌ Running Lights Over Night

More light is not always better.

Plants need a dark period to complete their natural growth cycle. Running lights all night can actually stress plants and reduce performance.

👉 What to do:
Run lights for 14–16 hours per day, then allow for complete darkness at night.

❌ Grow Lights Too Far Away (Indoor Growing)

Your plants rely completely on grow lights indoors. If the lights are too far away, they simply won’t get what they need.

Common signs:

  • Tall, thin, “stretchy” plants
  • Weak stems
  • Pale leaves

👉 What to do:
Keep grow lights close and equidistant from your plants and adjust as they grow.

❌ Letting Larger Plants Block Smaller Ones

Think of your plants like solar panels — they need access to light.

When larger plants (like tomatoes or cucumbers) grow above smaller ones, they can block light and slow growth below.

👉 What to do:
Follow a pyramidal planting approach:

  • Larger plants toward the bottom
  • Smaller plants toward the top

And prune when needed to keep light flowing through the tower.

❌ Towers Placed Too Close Together

If you’re running multiple towers, spacing matters.

When towers are too close, they can shade each other, especially in the morning and afternoon when the sun is at an angle.

👉 What to do:
Give your towers enough space so each one gets full sun throughout the day.

Troubleshooting Indoor Growing

If you’re growing indoors, lighting is just one piece of the puzzle. Issues like pollination and pests can also impact plant health.

👉 Read our full guide on troubleshooting indoor growing issues.

💡 Final Tip

If your plants aren’t thriving, light is almost always one of the first things to check.

In our experience, most issues aren’t caused by nutrients or water — they come down to not enough usable light reaching the plant.

Fix the light, and everything else gets easier.