Harley Smith

Harley Smith is the director of research for NPK Industries. A veteran in the hydroponics industry, Harley has more than 18 years of consulting and educating experience. He is regarded as an expert on plant nutrition and organic bio-stimulants, performing research and new product development in the US and Europe.

Articles by Harley Smith


Bring on the CO2 in Your Indoor Garden Bring on the CO2 in Your Indoor Garden Bring on the CO2 in Your Indoor Garden Bring on the CO2 in Your Indoor Garden


Providing your garden with extra carbon dioxide can have a dramatically positive effect on plant growth and yields. But like with nutrients...

Master the Art of Measuring EC Master the Art of Measuring EC Master the Art of Measuring EC Master the Art of Measuring EC


To maximize the benefits of growing hydroponically, it’s important to know how to fine-tune your nutrient regimen to ensure your plants are...

What To Do About Powdery Mildew What To Do About Powdery Mildew What To Do About Powdery Mildew What To Do About Powdery Mildew


Once a crop is infected with powdery mildew, it is always a battle to knock it down and keep it under control. The best defense is growing...

Start Clean & Keep It Clean in the Garden Start Clean & Keep It Clean in the Garden Start Clean & Keep It Clean in the Garden Start Clean & Keep It Clean in the Garden


Keeping a clean growroom is the first step towards ensuring more drastic measures are not necessary. Here are some tips to get your garden...

Why Your Garden Needs Phosphorus Why Your Garden Needs Phosphorus Why Your Garden Needs Phosphorus Why Your Garden Needs Phosphorus


Plants must have a steady supply of phosphorus from seed to harvest. It’s called the energy element for a reason! As one of the...

Humic or Fulvic Acid: What Kind are Your Plants On? Humic or Fulvic Acid: What Kind are Your Plants On? Humic or Fulvic Acid: What Kind are Your Plants On? Humic or Fulvic Acid: What Kind are Your Plants On?


Humic and fulvic acids are natural, complex molecules that improve the uptake of nutrients in both soil and hydroponics. Sourcing these...

Starting an Outdoor Hydroponic Garden Starting an Outdoor Hydroponic Garden Starting an Outdoor Hydroponic Garden Starting an Outdoor Hydroponic Garden


Summertime gives indoor growers the opportunity to take their hydroponic gardens outdoors, as plants, like their owners, also benefit from...

Test Tube Babies Test Tube Babies Test Tube Babies Test Tube Babies


Plant tissue culture micro-propagation may open the door for many new opportunities in hydroponics and computer-controlled agriculture.

Growing Strong Seedlings Growing Strong Seedlings Growing Strong Seedlings Growing Strong Seedlings


Giving your plants a strong head start is an important first step towards achieving success in your indoor garden. If your seedlings are...

Winter Lettuce Production Winter Lettuce Production Winter Lettuce Production Winter Lettuce Production


Head lettuces, such as iceberg lettuce, are not usually recommended for hydroponics, but there are many leaf lettuces and other leafy...

Improved Light Recipes for Indoor Gardens Improved Light Recipes for Indoor Gardens Improved Light Recipes for Indoor Gardens Improved Light Recipes for Indoor Gardens


Light is the limiting factor for most indoor gardeners, but it is possible to fine-tune your garden’s lighting needs to both save money and...

Building up the Brix for Healthier, Nutrient-Dense Crops Building up the Brix for Healthier, Nutrient-Dense Crops Building up the Brix for Healthier, Nutrient-Dense Crops Building up the Brix for Healthier, Nutrient-Dense Crops


The best organic farmers often boast about growing nutrient-dense, high-brix plants. Brix is a measurement of the sugar content in the sap,...

Caring For Your Mother Plants Caring For Your Mother Plants Caring For Your Mother Plants Caring For Your Mother Plants


Mother plants are stock plants specifically raised to provide cuttings for starting new plants. The cuttings, also known as clones, are...

Are All Calcium/Magnesium Supplements Alike? Are All Calcium/Magnesium Supplements Alike? Are All Calcium/Magnesium Supplements Alike? Are All Calcium/Magnesium Supplements Alike?


Calcium and magnesium are essential macro-elements, used in relatively large quantities by plants. In fact, plants typically take up more...

Boosting Your Harvest with Potassium Supplements Boosting Your Harvest with Potassium Supplements Boosting Your Harvest with Potassium Supplements Boosting Your Harvest with Potassium Supplements


Want to keep your garden growing strong during the fruiting and flowering process? Give your plants the right amount of potassium. During...

Yucca Extracts: A Gardening Secret from the Desert Yucca Extracts: A Gardening Secret from the Desert Yucca Extracts: A Gardening Secret from the Desert Yucca Extracts: A Gardening Secret from the Desert


When beneficial yucca extracts are applied to your favorite garden plants, they will get an extra boost of protection to help them deal...

Here Comes The Heat: Improving Your Plant’s Natural Tolerance to Environmental Stress Here Comes The Heat: Improving Your Plant’s Natural Tolerance to Environmental Stress Here Comes The Heat: Improving Your Plant’s Natural Tolerance to Environmental Stress Here Comes The Heat: Improving Your Plant’s Natural Tolerance to Environmental Stress


Stress isn’t all bad. In fact, a little stress can create a more robust plant and improve the taste of your crops. But a lot of angst makes...

Biogenic Silica Biogenic Silica Biogenic Silica Biogenic Silica


While not an essential element, silicon can positively impact your plants in many ways. Harley Smith discusses the benefits of feeding your...

Feeding Your Garden Cane Molasses Feeding Your Garden Cane Molasses Feeding Your Garden Cane Molasses Feeding Your Garden Cane Molasses


Adding a little cane molasses to your fertilizer regimen could result in a myriad of benefits for your plants. Here’s why.

Why Are My Leaves Turning Yellow? Why Are My Leaves Turning Yellow? Why Are My Leaves Turning Yellow? Why Are My Leaves Turning Yellow?


Yellowing leaves can be caused by just about anything that’s a little out of whack. Here we examine three common nutrient deficiencies.

Do You Know What’s In Your Water? Do You Know What’s In Your Water? Do You Know What’s In Your Water? Do You Know What’s In Your Water?


The results of a water test can show a grower how to customize their nutrient recipes and watering methods to optimize crop quality and...

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