Magnum Auto Seeds

Genetics & effects

Magnum Auto is a sativa-dominant autoflowering hybrid with approximately 70% sativa and 30% indica influence, plus ruderalis ancestry. Its exact lineage is not publicly established. The Kiwi Seed Bank catalogue presents it as an intermediate-level option for growers seeking vigorous growth, generous branching and an automatic flowering cycle.

Reported THC levels sit around 15–20%, while CBD is listed at 0–0.2%. Individual experiences vary, but users commonly describe the effects as uplifting, energetic, creative, euphoric and talkative. A more relaxed feeling may emerge later. The aromatic profile combines citrus and sweet notes with pungent spice and pine, consistent with a terpene mix associated with limonene, pinene and caryophyllene.

Explore autoflower seeds, high thc seeds, the New Zealand grow guide, and the planting calendar.

Explore autoflower seeds, high thc seeds, the New Zealand grow guide, and the planting calendar.

Growing in New Zealand

Magnum Auto can suit hot, dry areas as well as temperate regions and cooler locations with short summers. As an autoflower, it begins flowering according to age rather than a change in daylight hours. This makes timing important: steady warmth and long, bright days can help plants make the most of their compact life cycle.

For outdoor New Zealand gardens, spring planting generally falls between September and November. In cooler areas, waiting for settled conditions can reduce risk from cold nights, heavy rain and slow early growth. Choose a bright, sheltered position with free-draining soil and reliable airflow. Local microclimates, container size and seasonal weather can all influence height, timing and final output.

Indoor

Indoors, plants may reach up to 150 cm, so allow enough vertical room for lights and airflow. Gentle canopy shaping early in vegetative growth can help distribute light, but avoid repeated high-stress work because autoflowers have limited recovery time. Use an airy growing medium and containers that drain freely.

• Expected flowering phase: approximately 8–9 weeks.
• Reported indoor output: up to 400 g/m² in favourable conditions.
• Maintain consistent light, ventilation and root-zone moisture.
• Monitor dense flower sites closely where humidity is elevated.

A balanced environment matters more than aggressive feeding. Gradual changes can help avoid setbacks during the rapid transition into bloom.

Outdoor

Outdoors, Magnum Auto may grow up to 160 cm and produce up to 150 g per plant under favourable conditions. A sunny, north-facing location is useful in much of New Zealand. Shelter from strong wind without blocking air movement, and keep foliage away from persistently damp surfaces. In wetter districts, rain cover and wider spacing may reduce mould risk as flowers gain weight.

Because each plant follows its own age-based schedule, staggered spring starts can spread work across the season. However, cool conditions and limited sunlight can extend development or reduce overall vigour.

Harvest

The main New Zealand outdoor harvest period is March to May, although autoflower timing depends strongly on the planting date and local conditions. Check flower maturity rather than relying only on a calendar estimate. Aroma should become pronounced, flowers should look fully developed, and trichome colour can provide an additional maturity indicator. Keep harvested flowers in a dark, clean and well-ventilated space while moisture levels gradually stabilise. All height, timing, cannabinoid and output figures are approximate rather than assured.