You’ve never seen red and purple on your marijuana stalks before, but you’re noticing them now. It’s not always a bad thing, so don’t worry. Cannabis purple stems are frequently a genetics-related phenomenon rather than an obvious sign of a problem with your plants.

Join us to learn everything there is to know about cannabis plants’ purple stems. We’ll go over why they change colour, how to stop it from happening, and how to get rid of pigmentation after it has formed.

What do weed plants’ purple stems indicate?

Cannabis plants frequently display striking tones in their buds and leaves, but the branches and stems are less likely to do so. Cannabis plants can have red or purple stems and branches in addition to their usual green stems and branches.

One of two things could be the cause of red or purple weed stems:

• Environmental and genetic factors

Most of the time, these unusual colours are nothing to worry about, but occasionally they may indicate a deeper problem.

Why are the stems of my marijuana turning purple?

Several things can influence your marijuana stems’ colour. While some of these components improve the bag appeal of your buds, others harm your plants’ health.

The following are some possible reasons why cannabis stems are red or purple:

• Stress
• Transplantation or root shock following relocation
• Plagues or pests
• Problems with humidity or temperature
• Heat or light stress
• Overwatering

Light intensity

Your weed plants’ purple stems may indicate stress. Your crops can recover more quickly the sooner you find any problems. If you’ve recently come into contact with any of these potential stressors, it’s critical to inspect your plants:

The leaves and buds are the primary carriers of these vibrant hues, but the stems also can do so. Stems can become discoloured after prolonged exposure to intense light. This response is comparable to how sunburns human skin in some ways.

After defoliation, you might notice more pigmentation because trimming and pruning increase light penetration. Low-stress training methods also promote the growth of cannabis stems that are pink, red, or purple.

As long as your plants aren’t responding to stress from cannabis light burn, it’s normal for them to react in this manner to intense light exposure.

Keep an eye on your weed crops for a few days if you see red or purple stems after being in colder weather, especially if they don’t belong to the purple family. Growers purposefully subject these plants to cooler nighttime temperatures to highlight their stunning colours.

You should raise the temperature in your grow room or bring your plants indoors if you notice signs of stress. Generally, vegging should occur at temperatures between 18 to 29.5 ℃ and, during flowering, 20 to 25 ℃.

Pathogens 

 Plant diseases such as botrytis and fusarium can cause purple stems in cannabis. Since these pathogens quickly infect other crops, it’s critical to eradicate them as soon as possible.

Usually, botrytis affects larger cannabis plants, leaving a distinct brown line on the stems and branches. This fungus deprives your crops of nutrients and can significantly slow their growth. In severe circumstances, botrytis can cause your plants to perish.

Fusarium typically grabs hold of weak marijuana seedlings and knocks them over. Their stalks are attacked by this pathogen, resulting in brown, red, or faintly purple weed stems.

Nutritional deficiencies

Various symptoms, such as yellow and dry foliage and discoloured leaves and stems, indicate a lack of cannabis nutrients.

Before the leaves turn brown and brittle, phosphorus deficiency is mainly known to produce cannabis with purple stems. Red petioles, which are the stalks that connect a leaf to a stem, are frequently the result of magnesium shortages.

Nutrient deficiencies also cause damaged foliage and stunted growth, and discoloured stems. Any problems must be found as soon as possible and fixed.

pH levels

Your marijuana plants will remain happy and healthy with a slightly acidic pH. Your plants’ growth may be hampered, and their stems may turn purple if your pH errs too far off the mark.

The substrate you choose will determine the ideal pH for cannabis. A pH level of 6.5 is suitable for a soil medium, while a hydro level of 5.6 to 5.8 is perfect. Utilize a pH metre, and don’t forget to calibrate it regularly.

Genetics

Cannabis plants come in various colours due to their varied genetic ancestry. Unique pigments, ranging from orange and red to blue, green, and purple, can be seen in some strains.

An organic substance that gives red, purple, and blue pigmentation is called anthocyanin, and specific cultivars have higher concentrations of it. Concord grapes, red cabbage, eggplant, and other crops with comparable tones all contain this flavonoid.

Cooler temperatures encourage the growth of anthocyanin in your plants. Because of this, your weed plants’ buds, leaves, and stems all have vivid purple colouring. There’s no need to worry about your cannabis plants’ purple tint as long as they’re healthy and content—enjoy it!

How to avoid purple stems in cannabis

If your cannabis plants appear healthy, but the stems are turning purple, it may be a genetic predisposition. Wait a week or two before making any changes to see if they continue flourishing. You’re safe if they comply.

As soon as your crops change appearance, look for any telltale signs of stress to identify the issue. Once you understand the problem, you can take care of it and prevent it from happening again.

The following are some ways to avoid marijuana with purple stems:

• Maintain the proper pH levels.
• Give your plants the right nutrients to eat.
• Steer clear of temperature swings
• Uphold ideal humidity levels
• Watch out for light burn, transplant shock, and overwatering.

How to fix purple stems in cannabis

If your plants show signs of stress and you have cannabis with purple stems, you need to tend to them immediately. Determine which of the following circumstances is to blame as a first step:

• For your plants to recover from transplant shock, ensure they have good drainage, plenty of water, and aerated soil. Be prepared to wait a few days. For more information, see our reports on transplanting cannabis and autoflowering plants.
• Pests or plagues: Consider removing any severely damaged foliage from your crops after treating them with a suitable solution to encourage healthier portions to grow. An efficient way to lessen stress and quicken your plants’ metabolism is with a root booster.
• Problems with temperature or humidity: The best way to regulate temperature and humidity is to use a thermometer and hygrometer. A good ventilation system is also very effective.
• Light stress: Set your lights up properly to avoid leaf burn, and choose full-spectrum LED lights to prevent cannabis stems from turning purple.
• Use nutrient formulas with the right amounts of phosphorus, potassium, and nitrogen at every stage of your plant’s life to prevent nutrient deficiencies. Another crucial tool is a pH meter.

Purple cannabis stems: the lowdown.

If you notice red, blue, pink, or purple stems on your weed plants, there’s no need to be alarmed. This unusual discolouration, which is frequently the result of unique genetics, enhances the bag appeal of your buds.

Monitor your crops carefully and watch for signs of stress if they suddenly take on a strange hue. Make sure to address the problem as soon as you notice it to keep your cannabis plants happy and healthy.

Don’t forget to stock up on marijuana seeds at our seed bank and browse our blog at Mediseed Man for additional cannabis growing advice.