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

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The Quest RDS 10 features top-of-the-line Merv 7 filtration, and a high capacity pleated filter, the RDS 10 works to capture all dangerous particles, including pollen, dust, spores, and mold.
Hurricane Centrifugal Inline Fans are High-quality, commercial grade, and affordable centrifugal inline fans.
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With this Yellow Sticky Ribbon Trap, a non-toxic, double-sided sticky tape, you can monitor which pests seem to be the biggest issue, and you can start to take your greenhouse or garden back!
A hormone concentrate, root growth stimulant, and vitamin all in one, Hormex Concentrate works to stimulate growth of small feeder roots which can easily be damaged when you transplant.
The Danner Mag Drive 1800 clean technology, this pump contains absolutely no oil, and also was created with no seals that could eventually wear out or leak.
This pump is magnetically driven, contains no oil, and has absolutely zero seals that could wear out or leak.
Yet another perfect addition to your plant supplement routine, check out The Kraken from Nectar for the Gods.
Introducing the brand new 1000 Watt Double Ended HPS grow lamp from Hortilux: a top-of the line product featuring the exclusive Eye Hortilux spectrum.
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The MEGA LED Growlight from NextLight is a high intensity, full spectrum light guaranteed to replace any DE 1000w HPS on the market with a better energy efficiency rating and a larger footprint.
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The NextLight VEG8 Growlight is an energy efficient replacement light that performs just as good if not better than your existing fluoresent 8 tube T5.
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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.
To harvest your biggest yield yet, you're going to need plant stalks that can handle your heavy blooms and fruits. While your base nutrient series provides basic supplements necessary for strong stalk growth, Sturdy Stalk, a potassium silicate supplement from Emerald Harvest, gives your plants the extra boost they need to grow strong enough to withstand stressors from the environment and elsewhere.
$14.25 - $43.95
Introducing Emerald Harvest's Cal-Mag, a top of the line calcium and magnesium supplement perfect for perking your plants back up to a lush green state.
$29.95 - $109.95
Emerald Harvest's King Kola is a revolutionary bloom boosting supplement that leads the hydroponic industry by adding hemp seed flower for additional nutrients essential to your plants' bloom.

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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