Specializing in indoor gardening and hydroponics growing!

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Growco Indoor Garden Supply has been supplying growers with the best quality organic fertilizers, hydroponics systems, and indoor gardening supplies since we opened our first retail store in 1999! Large Orders

We now have two incredible retail stores in West Michigan, and a dedicated full-time warehouse for our internet customers. We stock all of the items that you'll find on this website at the lowest possible price, and we always ship orders out on same day we receive them or on the next business day! We specialize in complete growroom packages, and we will gladly take the time to help you build the growroom of your dreams! Large orders, pallets of soil- whatever you need for your indoor garden- you've come to the right place, we're here to help!

Emerald Harvest

Mills Nutrients

Featured Products

Unique double ended constructions allows doe maximum optical efficiency and uniformity.
Ozone is great at removing smoke, or strong pet smells. It kills mold and mildew in basements, and can eliminate powdery mildew on plants.
Heavy duty 5 gallon measuring bucket that is perfect for a variety of garden-related tasks.
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The Nextlight Mini LED Growlight is a small bulb that runs on just 150w, the Mini is a powerful LED Growlight that sports the full, highly-acclaimed NextLight full spectrum.

Newest Additions

?When your ?HM Digital Waterproof EC/TDS/Temp Combo meter needs a new sensor, this is the perfect fit. A Waterproof EC/TDS/Temp Combo Sensor.
The HM Digital Waterproof EC/TDS/Temp Combo meter is your one-stop shop for all kinds of testing in a variety of applications, including hydroponics, aquaculture, water purification, wastewater regulation, and more!
For a digital TDS meter than can go anywhere with you, check out this neat HM Digital Pocket-Size TDS Meter.
This sensor functions as the high-tech replacement Waterproof pH sensor for the compatible Waterproof pH Meter.
The HM Digital Waterproof pH Meter functions perfectly in a wide variety of applications, like water purification, hydroponics, wastewater regulation, and even aquaculture.
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The HM Digital pH HydroTester is the perfect pH meter for anyone looking to test applications like gardening, water ionizers, drinking water, hydroponics, and more!
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The RO-150 is a reverse osmosis water filtration system that removes 98% of all contaminants from 150 GPD of tap water, including chlorine.
The perfect addition to any compost tea, this product is loaded with carbohydrates, as well as proteins, organic acids, potassium, calcium, micronutrients, phosphorus, and magnesium.
Universal Cell Phone Illuminated Microscope with clip from Grower's Edge® makes sharing and storing magnified pictures of your plants a breeze.
$10.95 - $27.95
Specially formulated, derived from potassium hydroxide, and made with 36% soluble potash, CYCO pH Up helps you ensure optimal range of pH in your nutrient solutions by raising its total pH value.
$10.95 - $27.95
To get your maximum yield, you plants have to be able to absorb as many of the right nutrients as possible. Cyco pH Down is the product for you.
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Caster wheel set for Quest Dual Overhead Dehumidifier model 105, 110, 150, 155, 205, or 215,
Quest Dehumidifier replacement filter for the PowerDry 1300 and RDS10 Dehumidifiers.
Quest dehumidifier replacement filter for Overhead Units models 110 and 150.
Quest dehumidifier air filter for the PowerDry 4000, Dual Overhead units 105, 155, and 205.
The Quest PowerDry 4000 Pro Dehumidifier can dehumidify up to 22 gallons (176 pints) a day at 80ºF/60%RH, while consuming just 10 amps.

We always ship in heavy-duty plain brown boxes, and our 15 years of shipping experience help to insure that you will receive your order intact and undamaged every time! We warehouse all of our products, and pride ourselves in getting your order to you fast!

Our staff has many years of hands-on experience
helping customers build grow rooms, dial in nutrient programs, and make seriously productive gardens. Huge selection, low prices, and fast shipping- Growco wants to be your favorite grow shop! Let us help you learn to grow like a pro!

Private, secure online ordering. No registration needed to order. We strive for your complete satisfaction - we want to be your "go-to" source for performance gardening supplies!

Why shop at 4hydroponics.com?

  • FREE shipping on most orders $250 or more when delivered in lower Continental USA.
    (Sorry, Alaska and Hawaii not included.) Oversized or heavyweight items not included.
  • NO sales tax when delivery is outside of Michigan. In some states that's a 10% savings!
  • VERY competitive pricing.
  • No registration needed to place an order.
  • When we ship your order, magazines or catalogs are liberally included. (More info)
  • Read customer feedback here.

Shipping to Michigan? Expect delivery within 2 business days!

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Garden Watchdog Top 5 Organic Seeds in stock Hydro for Hunger participant OMRI Listed
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