Chemdawg 4

Chemdawg 4 is widely regarded as the 'grower\'s cut' of the Chemdog family — the phenotype that actually fills jars. Selected from the 2006 'Reunion' batch when Greg Krzanowski sent his last four original Dog Bud seeds to Joe Brand and P-Bud in Napa, Chem 4 was kept because it showed the most vigor and the heaviest production of any Chemdog phenotype. That reputation holds up in the garden, but this is not a beginner-friendly plant. It demands attention to environment, structure, and feeding from flip to chop.

The stretch is significant. Expect Chem 4 to double in height during the first three weeks of flower, driven by sativa-leaning vegetative expression despite its indica-dominant genetics. Internodal spacing runs long, and vegetative growth is rapid and vigorous, with deep forest-green foliage and wide indica-style fan leaves. Indoors, plants typically finish at four to five feet with training; left unchecked outdoors, they can reach ten to sixteen feet. Topping at the third or fourth node and aggressive low-stress training are essential to flatten the canopy. SCROG works exceptionally well with Chem 4\'s heavy lateral branching — it produces numerous cola sites when spread out. Defoliation in weeks two through four of flower is critical to open airflow through the dense canopy.

Yield is the headline. Indoor growers consistently report 350 to 450 grams per square meter under optimized conditions, with some pushing toward 550 g/m² in ideal setups. Outdoors, expect 25 to 30 ounces per plant by mid-to-late October at northern latitudes. The colas are massive — football-sized, tightly stacked, and incredibly resinous. That weight is precisely why structural support is non-negotiable: use a double trellis net indoors and large circular cages outdoors. Stems are stronger than Chem D but can still snap under the heft of fully developed buds.

Flowering runs nine to ten weeks, with most growers harvesting between days 63 and 77 of 12/12. Trichome maturity is the real clock. Target 70 to 80 percent milky-white heads with 20 to 30 percent amber for the classic Chem 4 stone — cerebral onset fading into deep physical sedation. Earlier harvest (all milky) shifts the effect more cerebral; later harvest increases the couch-lock factor.

Chem 4 is a heavy feeder with a fast metabolism. It maintains high nitrogen demand throughout its long flowering period and responds well to elevated EC levels. In coco or hydro, target 1.2 to 1.6 mS/cm in veg, ramping to 1.6 to 2.2 mS/cm during peak flower. Calcium-magnesium supplementation is mandatory, especially under LED lighting — 100 to 200 ppm CalMag at every watering prevents the mid-bloom deficiencies this cultivar is prone to. Maintain pH between 5.8 and 6.2 in soilless media, 6.0 to 6.8 in soil. In living soil or amended organic beds, Chem 4 thrives with heavy compost teas and top-dressed amendments that support its appetite.

Environment is where Chem 4 separates experienced growers from the rest. Daytime temperatures should hold at 68 to 80°F (20–26°C), with lights-off no lower than 63°F (17°C) — the plant is particularly cold-sensitive and will show premature senescence if night temps dip below that floor. VPD targets: 0.8 to 1.0 kPa in veg, 1.0 to 1.2 kPa in early flower, and 1.3 to 1.6 kPa in late flower. Relative humidity management is the single most important environmental variable: start at 55 to 60 percent in early flower, step down to 40 to 45 percent by mid-flower, and hold 38 to 42 percent through the final weeks. The dense bud cores are a botrytis magnet in humid conditions. Carbon filtration is essential — the terpene output is overwhelming, and odor management without it is impossible.

Under modern LEDs, push PPFD to 900 to 1,200 µmol/m²/s during peak flower. The plant handles high light intensity well and converts it into resin production, but only when VPD and feeding are dialed to match.

Disease pressure centers on powdery mildew and botrytis. Chem 4 has moderate overall pest resistance but a documented susceptibility to PM, particularly in humid environments. Preventive measures — potassium bicarbonate sprays in veg, aggressive canopy management, oscillating fans at multiple heights, and strict humidity control — are essential rather than optional. For pests, spider mites and thrips are the primary concerns; integrated pest management with biological controls (Phytoseiulus persimilis for mites, Orius insidiosus for thrips), sticky traps, and rigorous hygiene keeps populations in check.

For solventless extraction, Chem 4\'s dense trichome coverage translates well to ice water hash. Fresh-frozen material typically yields 3 to 8 percent by weight in bubble hash, with the 73 to 90 micron fractions producing the highest quality full-melt heads. Hash rosin pressed from that material at 160 to 180°F yields 60 to 80 percent by weight, preserving the strain\'s signature lemon-cleaner and diesel terpene profile.