How to grow the GMO cannabis strain from seed

By Rick Smith / November 2, 2026

To grow the GMO cannabis strain from seed, germinate a quality feminized seed, start it in a small pot, move it to its final container, veg it under 18 hours of light while you top and train it, then switch to 12 hours of light and 12 of dark to trigger flowering. Harvest when most trichomes look cloudy. Our GMO feminized seeds are photoperiod, so you decide when flowering starts, which gives you more control over plant size. This guide is for adults 21 and older where home growing is legal, and walks through every stage from seed to jar.

Meet GMO

GMO, also called Garlic Cookies, is a modern American hybrid that became famous in the late 2010s. It is widely described as a cross of Chemdawg and Girl Scout Cookies. The name has nothing to do with genetic engineering. It is short for Garlic, Mushroom, Onion, a nod to its savory, funky aroma.

The GMO seeds sold by Kind Seed Co are feminized photoperiod seeds. Feminized means nearly every plant should be female, so you are not sorting out males. Photoperiod means the plant keeps growing leaves and branches until you shorten its light to about 12 hours a day.

Typical ranges for GMO

Photoperiod plants like this are commonly listed at roughly 9 to 11 weeks of flowering after the switch to 12/12, and indoor height depends mostly on how long you veg and how much the plant stretches, often doubling in size after the flip. These are typical ranges reported for this kind of plant, not promises. Light, pot size, training and climate all move the numbers, and the GMO Feminized product page is the place to check current specs before you plan your space.

What to expect from GMO in the garden

GMO grows as a vigorous, indica leaning hybrid that can still stretch a lot after the flip, often more than growers expect. It is also widely described as a long flowering strain, so plan for a longer project than most modern hybrids. Buds are dense and coated in resin, and the aroma is among the loudest in any grow room.

In short, look for very frosty, dense buds on a plant that stretches hard and an aroma that leans pungent garlic, savory funk and diesel. Every plant is a little different, and your setup, light and care will shape the final result as much as genetics.

Before you start

Check your local laws. Grow only where home cultivation is legal under your state’s law and stay within your plant limit. You must be 21 or older. Federal treatment of cannabis seeds is also changing, so read our December 11 2026 seed rule explainer.
Pick your space. A 3×3 or 4×4 tent gives a photoperiod plant room to grow, and you will want extra height for the stretch.
Gather supplies. A quality full spectrum LED, a 5 to 7 gallon fabric pot, a light, airy soil or coco mix, a small fan, a pH meter and a timer.

Grow basics to read first

If this is your first grow, these guides cover the fundamentals that every strain needs:

Step 1: Germinate the seed

Soak the seed in clean, room temperature water for 12 to 24 hours, or until it sinks.
Move it to a damp paper towel inside a covered plate in a warm, dark spot.
Check daily. When a small white taproot appears, it is ready to plant.

Handle the taproot gently and plant it root down about a quarter to half an inch deep.

Step 2: Start small, then transplant

Photoperiod plants handle transplanting well. Start the seedling in a small pot or solo cup so roots fill it quickly, then move it to a 1 gallon pot and finally to its 5 to 7 gallon home. Transplant when roots reach the sides but before they circle. Water the new pot lightly so roots spread out to find moisture.

Step 3: The seedling stage

Run 18 hours of light and 6 of dark.
Keep the light at a gentle intensity and a comfortable distance.
Water lightly in a small circle around the stem.
Keep humidity moderately high and temperatures comfortable.

Step 4: Vegetative growth

This is where you shape your GMO plant.

Top the plant. When it has five or six nodes, cut the main stem above the fourth or fifth node to create two main colas.
Train the branches. Use soft ties or a scrog net to spread branches into a flat, even canopy.
Feed for growth. Use a nitrogen rich veg nutrient at a modest strength and increase slowly.
Water wisely. Let the top inch of soil dry before watering again.
Decide when to flip. Most photoperiod plants stretch after the switch. Flip when the plant is roughly half the final height you can fit.

Step 5: Flip to flower

Change your timer to 12 hours on and 12 hours off. Keep the dark period truly dark, since light leaks can confuse the plant.

Shift nutrients. Move toward a bloom formula with more phosphorus and potassium.
Manage the stretch. Keep tucking branches under the net for the first few weeks.
Lower humidity. Keep air moving and humidity lower as buds bulk up.
Defoliate lightly. Remove large fan leaves that block bud sites.

Managing the stretch

GMO can grow a lot taller after flowering starts. Plan for it from the start. Top early, train branches outward, and flip earlier than you would with a compact indica. Our guide on how to control and prevent stretching covers light distance, spacing and training in more detail.

Keeping the smell under control

GMO is known for a loud aroma, and it gets stronger every week of flower. An inline exhaust fan pulling air through a carbon filter is the most reliable way to keep it in the tent. Size the fan for your tent volume, keep the filter close to the top of the tent where warm air collects, and replace the carbon on schedule. Our guide on how to build a DIY carbon filter walks through a budget option.

GMO specific tips

Flip early. Many growers flip GMO at about a third of their final available height because of its strong stretch.
Plan your schedule around a longer than average flowering period, and let the trichomes decide the harvest.
Run a strong carbon filter from day one of flower.

Step 6: Know when to harvest

The best way to time your harvest is to look at the trichomes, the tiny resin glands on the buds, with a jeweler’s loupe or clip on macro lens.

Clear trichomes: not ready yet.
Mostly cloudy: many growers harvest here.
Some amber: some growers wait for a portion of amber.

Pistils also darken and curl as harvest nears. Use the product page’s flowering time as a guide, but let the trichomes have the final say.

Step 7: Dry and cure

Cut branches and hang them in a dark space with gentle airflow and moderate humidity.
When small stems snap rather than bend, trim and place buds in airtight glass jars.
Open the jars briefly each day for the first couple of weeks, then less often.

A slow dry and patient cure bring out the full GMO aroma.

Growing GMO outdoors

Where outdoor home growing is legal, a photoperiod GMO plant follows the sun. It grows through late spring and summer and starts flowering as days shorten in late summer. Plant after your last frost in a sunny, private spot, use a large container or well prepared bed, and plan for a fall harvest before heavy rain or frost. Keep plants out of public view as your state requires.

Photoperiod or autoflower?

Photoperiod GMO gives you control over size and timing, plus room for topping and training. It also takes longer and needs a light schedule change. If you want a faster, simpler grow, browse our autoflower seeds.

A simple GMO shopping list

One or two GMO seeds, within your legal plant limit
A 5 to 7 gallon fabric pot per plant, plus a small starter pot
Light, airy soil or a coco and perlite mix
A full spectrum LED light sized for your tent
An oscillating clip fan and a small exhaust fan with a carbon filter
A pH meter or test kit
Sharp, clean scissors for topping and a scrog net
A jeweler’s loupe for checking trichomes
Airtight glass jars for curing

Common GMO growing mistakes

Overwatering seedlings. Small roots in a big pot drown easily.
Overfeeding. Burnt leaf tips are a sign to back off.
Flipping too late. Photoperiod plants stretch in early flower, so leave headroom.
High humidity in late flower. Buds need good airflow.
Harvesting by calendar alone. Check trichomes.

Frequently asked questions

Why is it called GMO?

GMO stands for Garlic, Mushroom, Onion, a reference to its savory aroma. It has nothing to do with genetic modification.

Does GMO take long to flower?

It is widely described as a longer flowering strain than most modern hybrids. Check the product page and judge by trichomes.

How long does GMO take from seed to harvest?

It depends on how long you veg and on conditions. Check the product page for the expected flowering time after the flip and confirm with trichomes.

What light schedule does GMO need?

Run 18 hours on and 6 off in veg, then switch to 12 on and 12 off to start flowering.

Can I grow GMO in a small tent?

You can, but photoperiod plants need training and an early flip to fit. A 3×3 or 4×4 tent is more comfortable.

Start your GMO grow

With its distinctive aroma and very frosty, dense buds on a plant that stretches hard, GMO has earned a loyal following. Pick up GMO seeds from Kind Seed Co to start your next grow, see our Cookies strains collection for similar options, or browse the full Kind Seed Co shop. For the basics, read our ultimate beginner’s guide to growing cannabis. Kind Seed Co sells only to adults 21 and older.