Grow Diary Granddaddy Purple

Granddaddy Purple – Week #8 of Flower (Late Flower)

Week eight of flower saw Granddaddy Purple firmly establish itself in the early stages of late flower, with continued calyx expansion, increasing resin density, and a clear progression of natural senescence across older fan leaves. Structural support remained effective throughout the canopy, requiring no additional reinforcement as flower mass continued to build.

Environmental management was a primary focus this week. With multiple strains at different stages sharing the same tent, conditions were actively balanced to support ripening plants while allowing Granddaddy Purple to continue maturing without unnecessary stress. Daytime canopy temperatures generally held in the low-to-mid 70s°F, with relative humidity maintained in the low-to-mid 40% range. These conditions were selected to preserve resin integrity, maintain transpiration, and minimize any risk of excess moisture during late flower.

Light intensity remained stable, with canopy PPFD averaging between approximately 925 and 950, resulting in a DLI of roughly 40–42. This level continues to support flower development while avoiding excess intensity late in the cycle. UVA exposure was deliberately reduced over the course of the week, stepping down from approximately 120 minutes at the beginning of the week to about 45 minutes by week’s end. This reduction was made to accommodate a companion plant in active ripening and to prevent unnecessary stress during this stage of development.

Nutrient strategy continued its transition into late flower. Early in the week, feeding consisted of a blended 50/50 mix of mid- and late-flower nutrients at medium strength, delivering approximately 805 ppm. By the end of the week, Granddaddy Purple was fully transitioned to late-flower nutrients at medium strength, with feed strength reduced to approximately 640 ppm. This adjustment reflects the plant’s shifting nutritional demand as senescence advances, while still providing sufficient support for continued flower maturation. The plan is to maintain light late-flower feeding through at least the coming week.

Watering remained consistent, with irrigation volumes adjusted as needed to periodically achieve moderate runoff while avoiding excess moisture retention in the medium. Uptake has remained steady, and no signs of nutrient stress, lockout, or imbalance were observed.

While a formal trichome assessment was not performed this week, visual indicators suggest continued progression toward ripening. Buds remain dense and well-formed, with heavy trichome coverage across calyxes and sugar leaves. Senescence is increasingly evident on older fan leaves, particularly in the mid and upper canopy, consistent with normal nutrient reallocation at this stage. This fade is expected and welcomed as part of the plant’s natural finish.

Aromatically, Granddaddy Purple continues to intensify. Sweet fruit and dark berry notes dominate, with a rich, heavy character that has become more pronounced as the plant advances through late flower. Overall, the plant is transitioning smoothly toward ripening, with current strategies centered on stability, stress avoidance, and preserving resin and terpene quality heading into the final phase of flower.