Plants don't smell (third week of flowering)

Hey Growmie, If your plants are in the third week of flowering and still not smelling much, it's not necessarily a bad sign—yet. Here are some factors to consider and possible reasons for the lack of odor: Normal Flower Development Timing Week 3 of flowering is still fairly early. Most strains really start to ramp up trichome and terpene production in weeks 5–7. Smell often explodes later, especially in photoperiod plants. Genetics Some strains are naturally low-odor, especially certain phenotypes bred for stealth or light terpene expression. If this has happened before with other plants, check if they were similar or related genetics. Nutrients & Microbes Advanced Nutrients is generally solid, but overly sterile soil or lack of beneficial microbes can reduce root health, which in turn impacts terpene expression. Consider adding something like microbial inoculants (e.g., Great White, Recharge) to boost rhizosphere activity. Airflow & Carbon Filters Strong carbon filters or air exchange setups can scrub smells before you even notice them. This is especially common in sealed grow tents.Try standing near the buds without exhaust on for a minute—do you smell anything directly? Nutrient Balance Too much nitrogen in flower can delay or mute terpenes. Make sure you're using a proper bloom formula with reduced nitrogen and increased P/K. Terpene Production Boosters You could try: Bud Candy, Terpinator, or Sweet—these products aim to boost terpene production. Or natural routes like molasses to feed soil microbes (1 tsp per gallon every other watering). If your plants are healthy, flowering, and forming buds, lack of smell right now isn’t cause for panic. Terpene production is one of the last big things that kicks in as buds mature.

You’re just starting the flower cycle. Trichomes won’t start to develop along with terps for another couple of weeks. Then the smell should start to get stronger. This does have a lot to do with environmental conditions and genetics. Do you part to provide perfect conditions for growth, and she will reward you with her best possible genetics.

What are terpenes? What are their purpose in nature? What mechanisms control terpene accumulation in cannabis plants? What is a volatile organic compounds? When does a cannabis plant release VOC? What part of plant releases VOC? What temperature do terpenes profile start to degrade? Are there environmental light signals you can signal to accumulate terpenes? Are there any hormones that can be manipulated to prevent release of VOC at same time as signalling accumulation? How important are microorganisms to taste and flavour profiles? How important is sulhpur in the formation of IPP prior to week 3 of flower, in production of terpenes? Can you use Systemic Induced Resistance (ISR) to increase terpenes? Here's a more detailed explanation: 1. Systemic Acquired Resistance (SAR) and Induced Systemic Resistance (ISR): SAR: This is a long-term immunity in plants that is triggered by pathogens and is often linked to the salicylic acid (SA) pathway. It involves the systemic activation of defense mechanisms in undamaged parts of the plant, preparing them for future attacks. ISR: This is a similar systemic response, but it's triggered by beneficial microbes, and it can involve different signaling pathways, like jasmonic acid (JA). 2. Terpenoids as Signaling Molecules: Herbivore-induced plant volatiles (HIPVs): These volatile terpenes are released in response to herbivore attack and can attract beneficial insects that prey on the herbivores, providing indirect defense. Oviposition-induced plant volatiles (OIPVs): These volatile terpenes are released in response to herbivore egg-laying and can also induce defense responses in the same plant. Plant-to-plant signaling: Volatile terpenes can act as airborne signals that can induce defense responses in neighboring plants, a phenomenon called plant-to-plant communication. 3. Factors that Trigger Terpene Production: Pathogen infection: Plants can produce volatile terpenes in response to pathogen attack, which can attract beneficial insects or directly inhibit the pathogen. Herbivore attack: Volatile terpenes are released in response to herbivore feeding, and these volatiles can attract natural enemies of the herbivores. Beneficial microbes: Some beneficial microbes can stimulate terpene production by activating the plant's defense mechanisms. Abiotic stress: Conditions like drought, salt stress, and temperature fluctuations can also induce terpene production, though the response can be species-specific. 4. The Role of Terpenoids in Plant Defense: Direct defense: Some terpenes have direct antimicrobial or insecticidal properties. Indirect defense: Others attract beneficial insects that prey on herbivores or pollinators. Systemic defense: Terpenoids can act as systemic signals, activating defense responses in other parts of the plant, even those that are not directly attacked. 5. Examples of Terpene Production: Monoterpenes: These are a common type of terpene that can be released by various plants in response to different stressors. Sesquiterpenes: These are another group of terpenes that can be produced by plants in response to stress. Diterpenes: These are also a group of terpenes involved in plant defense. In essence, terpenes play a crucial role in plant defense by acting as both direct and indirect defense mechanisms, as well as signaling molecules that can activate systemic defenses within and between plants. No quick and easy solution, study hard, knowledge is king. More you understand the underlying mechanisms the better you can manipulate the process for your benefit.

Hey growmie week 3 is still early for many strains to start smelling, From your pics, they’re just starting proper flower structure, so give it another 7–10 days. That said, if this keeps happening every run, the common factor is likely the genetics. Some strains are just low-odor by nature and won’t push terpenes hard indoors, even under good conditions. Environment and health look solid though, so I’d hold off worrying until you’re deeper into Week 4. Hopefully the funk still kicks in.