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.
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

To protect your plants from overheating, and potentially even fire, check out the Titan Controls Zephyr 2 - High Temperature Shut-Off with Delay.
?If you're looking for a digital timer to handle multiple appliances or units in your hydroponic system, lighting equipment, pump, or other large scale gardening operation, then you need the Blueprint BDT-2.
For a timer that can enforce any schedule you set, look no further than the Blueprint BDT-1.
$25.95 - $425.00
A pH stable, easy-to-use nutrient specifically formulated for the grow phase of your plants, Gro Terra contains a whole host of essential macro and micro elements necessary for exceptional plant development.
$25.95 - $425.00
Supernatural Bloom Terra contains essential minerals as well as all the trace elements necessary for a large, vigorous bloom phase, Bloom Terra is affordable, and pH stable.
$16.95 - $56.95
Organic Bountea SuperStart brings the nutrients your plant needs to grow and thrive.
Organic Bountea's Better Bloom is a natural, organic fertilizer to help boost your plants to their best bloom.
$20.95 - $56.50
Bountea Root Web is the prefect choice to protect your seeds, trees, and lawn from fungal disease.
$16.95 - $56.50
Bountea M3 uses nitrogen and other organic minerals to strengthen your plants and increase your plants growth.
$16.95 - $56.50
Bountea’s Fungal Activator delivers beneficial fungus to your woody-stemmed plants through compost tea.
$16.95 - $56.50
Bountea’s Bioactivator boosts beneficial bacteria and microorganisms to give your compost tea and extra boost.
$8.95 - $58.50
A combination of soluble seaweed extract and seven micronutrients, BioAg CytoPlus is an excellent source of beneficial organic compounds, including humic and fulvic acids.
$6.50 - $28.50
BioAg Ful-Humix is a water soluble humic powder and soil/nutrient activator. It increases nutrient efficiency and uptake, increases cellular activities at all levels.
$22.95 - $53.50
Xtreme Gardening Mykos WP (Wettable Powder) provides an effective Biological Inoculant that may be injected through a sprayer, applied in hydroponic reservoirs, and used as a seed or cloning treatment.
A fertilizer specially formulated to bring out the best in your Japanese maples and other low pH feeders, like lilies evergreens, hydrangeas, junipers, dogwoods, and flowering ornamentals.

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.
Michigan

Shipping to Michigan? Expect delivery within 2 business days!

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