Ultimate Guide: How to Tell When Your Outdoor Cannabis Plant Is Ready to Harvest

Table of Contents

• How Long Does It Take for Cannabis to Grow?
• Tips and Tricks for Harvesting Outdoor Cannabis
• How to Tell Cannabis Is Ready for Harvesting?
• When to harvest outdoor cannabis according to pistil (hair) color
• When to harvest outdoor cannabis according to trichome appearance
• When to harvest outdoor cannabis, autoflower seeds vs photoperiod feminised seeds

Knowing what week your plant is on can save you the headache of taking educated guesses as to when your plant is ready to cut.

Harvesting at the right time is crucial when it comes to growing cannabis. If you harvest too early, you will have premature buds which leads to a poor product and a smaller yield. Harvest too late and the potency of your weed takes a steep decline or turns to rot.

The telltale sign of harvest-ready weed is when the hairs of the plant, or pistils, have fully darkened and curled in. If your buds are looking thick and dense, but there are still some straight white pistils, it's not time yet.

"The most reliable way to tell if your plant is ready to harvest is with a microscope or a good quality close-up photo," Feuer says. "You want to look at the trichome heads to see when they go from clear to amber. The second way, if you only have the naked eye, is to see when 80 percent of the hairs have gone from white to red."

Maybe you prefer one way or the other, maybe it's somewhere in between. Many believe that the bud has different effects depending on when you harvest. On the roof of WW, our pistils are about 50 percent transitioned and we are looking to harvest sooner rather than later, for fear of bud rot.

How to Tell Cannabis Is Ready for Harvesting

When it comes to the optimal time to harvest marijuana plants, instead of looking at the entire plant, it’s more beneficial to look at the color of its trichomes and leaves and the shape of its buds.

Trichome Color

It’s inaccurate to assume that a cannabis plant is ready to harvest because it’s in its flowering period and has started producing buds. Instead, look at the color and development of its trichomes.

Trichomes are primarily found on the plant’s flower and leaves (sometimes, they are called “sugar leaves” when covered in these substances).

Doing this with the naked eye can be hard, so use a magnifying glass, digital microscope, or jeweler’s loupe to get a closer look.

• Clear trichomes: The hairs are translucent, and the plant still produces resin in its glands. This is not the ideal time to harvest, and the plant’s cannabinoids and terpenes are not at peak concentration.
• Milky/cloudy trichomes indicate that cannabinoid production is at its peak. A cannabis plant is usually ready to harvest when half of its trichomes resemble cloudy, white hairs. This can result in a more uplifting, energizing effect for some users.
• Amber trichomes: Amber trichomes tend to indicate that the THC/THCA in cannabis has started to deteriorate, meaning there may be more cannabinol (CBN) in the flower. CBN can have sedative effects; many report feeling those effects with amber trichomes.

Many users like a mix of milky and amber trichomes, although the split proportions come down to personal preference. Some prefer all or mostly cloudy with few amber trichomes for more cerebral or psychoactive effects. Others prefer a 50:50 split between cloudy and amber trichomes for a balanced head and body effect. Others prefer 60% to 70% amber trichomes for a less stimulating, more sedative effect.

Leaf Color

Healthy cannabis plants should have fan leaves that are a vibrant green color.

A color change to yellow or brown leaves indicates the plant has nutritional deficiencies or root rot. Feeding the plant too many nutrients (“overfeeding” or “nutrient burn”) is also a problem that can discolor and dry out the plant’s leaves. If growing in soil or a soil-coco mix, it is best to be sparing with nutrients and let the soil do most of the work.

If your plant starts to brown after all the trichomes have developed, the plant is probably dying. These plants should be harvested as soon as possible!

Bud Shape

Different strains of cannabis can produce different bud shapes and densities. In general, cannabis buds are ready to harvest when they thicken and their white pistils start to darken.

Tips and Tricks for Harvesting

There are many different tips and tricks for harvesting, which can depend very much on the growing environment and medium. Here are some pro tips and tricks that can help regardless of your growing environment:

• Do not feed the plant any nutrients in the last week of flowering. You will want to flush out all nutrients in the growing medium so it doesn’t end up tainting the buds.
• Low-stress training (LST) can help increase the plant’s yields and vigor. LST is the practice of gently bending stems and tying them in place to increase bud production. This is more effective in an indoor environment.
• Be patient and wait for the right time. Harvesting too early can result in a less potent product, while harvesting too late can lead to a decrease in THC content and flavor.
• Use a sharp, clean pair of pruning shears or scissors to make clean cuts when harvesting. This reduces the risk of damaging the plant and introducing contaminants.

When to Harvest Outdoor Cannabis According to Pistil (Hair) Color

Another way to determine when to harvest your outdoor cannabis plant is by closely observing the color of the pistils (hairs) on the buds. The pistils go through several color changes as they mature, and each stage provides different effects and flavors:

• White pistils: At this stage, the pistils are still white and sticking out. Harvesting at this point will result in a more cerebral, uplifting effect and a lighter flavor profile.
• Orange or brown pistils: As the pistils start to change color to orange or brown, the buds are approaching maturity. Harvesting at this stage typically provides a balanced high and flavor profile.
• Red or amber pistils: When the pistils turn red or amber, the buds are at their peak ripeness. This stage often yields a more relaxing, sedative high and can have a richer, deeper flavor.

Choose the pistil color that aligns with the effects and flavors you desire from your cannabis.

When to Harvest Outdoor Cannabis According to Trichome Appearance

Trichomes, the tiny resinous structures on cannabis buds and leaves, can provide valuable insights into the plant's readiness for harvest. To determine the optimal time to harvest based on trichome appearance, you'll need a magnifying tool, such as a jeweler's loupe or a digital microscope. Here's what to look for:

• Clear trichomes: When the trichomes are mostly clear, the plant is not yet ready for harvest. The cannabinoids are still developing, and the effects will be less potent.
• Milky trichomes: When a significant portion of the trichomes turns milky or cloudy, the plant is approaching its peak potency. This stage is preferred by those seeking a balanced high.
• Amber trichomes: If you notice amber-colored trichomes, it indicates that the THC is degrading into CBN (cannabinol). Harvesting at this stage may result in a more relaxing and sedative effect.

Your choice of harvest time can influence the overall effects and flavors of your cannabis, so select the trichome appearance that aligns with your preferences.

When to Harvest Outdoor Cannabis: Autoflower Seeds vs. Photoperiod Feminised Seeds

The timing of harvest can vary depending on the type of cannabis seeds you're growing: autoflowering (autoflower) seeds or photoperiod feminized seeds. Here's how to determine the right harvest time for each:

Autoflower Seeds:

Autoflowering cannabis plants have a predetermined life cycle and will automatically transition from the vegetative stage to the flowering stage. This makes timing the harvest more predictable:

• Most autoflower strains are ready to harvest in about 10 to 12 weeks from seed germination.
• Observe trichome and pistil color changes as mentioned earlier to fine-tune the harvest timing for your desired effects.

Photoperiod Feminized Seeds:

Photoperiod feminized cannabis plants require a specific light schedule (12 hours of light and 12 hours of darkness) to trigger the flowering stage. Harvesting these plants requires careful consideration:

• Timing can vary depending on the strain, but it often falls within 8 to 12 weeks after switching to the flowering light schedule.
• Use trichome and pistil color changes as your primary indicators of readiness for harvest.

Keep in mind that these are general guidelines, and factors such as strain genetics, growing conditions, and personal preferences can influence the ideal harvest time. Regularly monitoring trichomes and pistils is the key to achieving the desired effects from your outdoor cannabis plants.

Happy harvesting!