Can You Grow Autoflower Hydroponically?

Autoflower cannabis thrives in hydro setups. When you grow in water, your plants can grow faster and taller because they can easily absorb the necessary nutrients and oxygen. Growing hydroponically also gives you more control over all the variables involved in cultivating cannabis.

There are several different hydroponic methods you can try. One of the most common is ebb and flow (or flood and drain). In this system, a reservoir under the plants fills with water containing a nutrient solution, then gradually drains. Ebb and flow (or flood and drain) requires a medium like coco fiber, rockwool, or perlite to stabilize your plants.

Deep water culture (DWC) is another popular option. In this system, the plants have part of their roots continuously submerged in a mixture of water and nutrients. Deep water culture (DWC) is one of the easier cultivation methods.

Aeroponics is another way to grow autoflowers without soil. In an aeroponic system, the roots grow in air and are constantly sprayed with a nutrient and water solution. This method allows for good nutrition and plenty of oxygen, but the equipment can be expensive.

Differences Between Hydro Cultivation and Soil Cultivation

Hydro cultivation allows you precise control over the proportion of necessary nutrients. Cannabis plants need different ratios of potassium, nitrogen, and phosphorus at different stages of growth, but it’s hard to measure the precise amount of nutrients in soil.

Autoflower cannabis grown in soil will expend more effort to make its roots grow to find nutrients. In a hydro system, the plants don’t have to do this and can put that energy toward high production and heavy buds instead.

Growing hydroponically also reduces the risk of insects and diseases.

What Do Autoflowering Seeds Need to Be Grown in Hydro?


Water is the most obvious ingredient for growing autoflowers hydroponically. Be sure to check your pH levels daily and keep the pH between 5 and 6 so your plants can absorb nutrients correctly. You can use a pH-adjusting solution to raise or lower the pH.

Water Pump

A water pump circulates the water in your grow system to prevent it from becoming stagnant and developing algae or mold. You may also need an air pump or air stone to add oxygen to the water.


To get the best potential harvest from your autos, you need good nutrition. Like most cannabis plants, autoflowers need plenty of nitrogen and potassium in the seedling phase, more nitrogen to produce healthy leaves in the vegetative stage, and lots of phosphorus and potassium in the flowering phase. Make sure you use nutrients that can fully dissolve in hydro systems, or you could clog your equipment.

A PPM meter is highly recommended to measure nutrient levels. Gradually increase the concentration of nutrients as your autos grow – aim for 100-250 PPM in the seedling phase, 300-700 PPM in the vegetative phase, and 750-1600 PPM in the flowering phase, followed by a flushing phase with no added nutrients before harvest.


Good lights are essential for healthy leaves, heavy buds, and high production. Fortunately, the lighting requirements when you grow in water are no different than soil. You can use LED or HPS lamps, but make sure they are full-spectrum. Be sure to give your autoflowers at least 18 hours of light for the best potential harvest.

Tips for Growing in Hydroponics

When growing autoflowers in hydroponics, you’ll get much better results if you maintain the correct pH levels (between 5 and 6). If the pH is outside of that range, the plants won’t be able to absorb nutrients.

Hydro setups are prone to developing bacteria and algae. To prevent this, clean your system thoroughly with bleach or hydrogen peroxide between grow cycles.

The 5 Best Autoflowering Strains for Hydroponic Growing

You can grow any strain successfully in hydro, but these five big yielders are highly recommended.

  1. Green Crack Auto : A sturdy, highly productive strain with a spicy mango taste
  2. Lemon AK Auto : High THC levels (up to 24%) and a very fast grower
  3. Strawberry Banana Auto : One of our favorite big yielders with high potency (27%)
  4. Rhino Ryder Auto : A pleasant physical buzz with moderate THC levels (20%) and 1.2% CBD
  5. Northern Lights Auto : A great strain for beginners that produces a powerful couch lock effect

SeedsPlug sells all these strains and more with convenient, discreet shipping to Montana, Vermont, Pennsylvania, and across the U.S.

Final Thoughts

Although some people consider growing in soil an easier cultivation method, growing hydroponically can produce much better results that make it worth the effort. Once you’ve decided on the perfect hydro setup, be sure to pair it with the best autoflower seeds. SeedsPlug offers high-potency seeds with a germination guarantee. We ship throughout the U.S., from Pennsylvania and Vermont to Montana and everywhere in between.

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