Auto Purple Amnesia by Short Stuff Seedbank: A Comprehensive Strain Guide - Blog - JointCommerce
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Auto Purple Amnesia by Short Stuff Seedbank: A Comprehensive Strain Guide

Ad Ops Written by Ad Ops| December 04, 2025 in Cannabis 101|0 comments

Auto Purple Amnesia is an autoflowering hybrid bred by Short Stuff Seedbank, a pioneer in compact, fast-finishing cannabis cultivars. As its name hints, it fuses the color-splashed allure of purple genetics with the cerebral spark of the Amnesia family, then layers in ruderalis to power automatic...

Overview

Auto Purple Amnesia is an autoflowering hybrid bred by Short Stuff Seedbank, a pioneer in compact, fast-finishing cannabis cultivars. As its name hints, it fuses the color-splashed allure of purple genetics with the cerebral spark of the Amnesia family, then layers in ruderalis to power automatic flowering. The result is a plant that shifts from seed to harvest without photoperiod changes, typically finishing in under 11 weeks while displaying striking pigments and a terpene bouquet that toggles between citrus-bright and spicy-earthy.

Growers are drawn to Auto Purple Amnesia for its balance of effects and its versatility in small spaces. Expect a plant that remains relatively compact yet branches well, delivering dense, resinous buds with vivid hues under cooler night temperatures. Most cultivators report approachable potency, buoyant mood elevation, and a clear, creative headspace paired with a physically calming finish.

From a user experience perspective, Auto Purple Amnesia sits at the lively intersection of uplifting and soothing—ideal for daytime creativity or late-afternoon wind-downs. Its heritage is ruderalis/indica/sativa, aligning with Short Stuff Seedbank’s track record of multi-faceted autos. For home and craft growers, it provides a forgiving cultivation curve, attractive bag appeal, and a terpene profile that plays well across vaporization and combustion.

History and Breeding (Short Stuff Seedbank)

Short Stuff Seedbank emerged during the first wave of modern autoflower development in the late 2000s and early 2010s, championing compact cultivars that could reliably finish under fixed light cycles. Auto Purple Amnesia fits squarely into this mission, offering growers a way to capture Amnesia’s famed uplift in a fast, discreet plant. The strain’s creation blends Amnesia-derived genetics with purple-leaning lines, then stabilizes the automatic trait via Cannabis ruderalis.

In practice, breeding an autoflower like this involves multiple backcrosses to lock in the auto-flowering allele while preserving flavor, color, and effect. Anthocyanin expression (the purples) is favored, while the Amnesia family contributes citrus-forward terpenes and a lucid head high. Over several filial generations, breeders target consistent height, a predictable timeline, and a cannabinoid profile that won’t swing wildly from plant to plant.

Although release dates are seldom formalized for niche autos, Auto Purple Amnesia is widely recognized as a 2010s-era cultivar. It mirrors broader market trends of the time: pack visual impact into autos, maintain yield, and avoid the harshness that once plagued early autoflowers. Today, it stands as a practical entry point for growers wanting a colorful Amnesia-inspired auto without the long flowering periods associated with photoperiod sativas.

Genetic Lineage and Heritage

The lineage is best summarized as ruderalis/indica/sativa, with the sativa side strongly influenced by Amnesia-family genetics. On the other axis, purple lines—often indica-leaning—impart anthocyanin production, shorter internodes, and a denser bud structure. Ruderalis adds the autoflowering trait, initiating bloom by age rather than day length.

From the Amnesia side, expect a prominent limonene/terpinolene-driven scent and an upbeat, creative cerebral tone. From the purple lineage, anticipate myrcene and caryophyllene accents, deeper coloration in bracts and sugar leaves, and an earthy-spicy undertone. Combining these creates a terpene stack that can read as lemon-peel meets forest floor, with floral and berry flickers depending on phenotype.

Comparable seed listings reinforce this blend of attributes. Vendors frequently describe Amnesia lines as having high THC and low CBD, with energizing and euphoric effects, while purple autos often note earthy-spicy flavors around 12–18% THC. Within that spectrum, Auto Purple Amnesia typically lands near the middle: flavorful, balanced, and reliable in finishing time.

Appearance and Morphology

Auto Purple Amnesia tends to stay compact, with many indoor plants landing between 60 and 100 cm in height. In small containers (7–11 liters), expect a main cola with several satellite branches, while larger pots encourage a bushier profile with more lateral sites. Internodal spacing is moderate, allowing light penetration without the lankiness of pure sativas.

As anthocyanins ramp up late in bloom, bracts and sugar leaves can shift from lime green to plum and eggplant hues. This color change is more intense when night temperatures dip 3–5°C below daytime highs, especially during the final three weeks. Bright orange pistils stand out against the dark backdrop, and resin coverage is typically dense, giving buds a frosted sheen.

Bud structure is medium-density—chunkier than classic haze flowers, but not as rock-hard as some indica-dominant autos. Trichome heads are plentiful, often clouding over without the heavy amber shift that indica lovers chase. The overall effect is a striking, high-contrast canopy that visually signals ripeness as the purple tones deepen.

Aroma

Aromatically, Auto Purple Amnesia is a two-voice chorus: citrus-bright top notes complemented by earthy, spicy base tones. The Amnesia influence leans toward lemon-zest and sweet grapefruit, consistent with limonene- and terpinolene-forward chemotypes. The purple side supplies damp forest, cracked pepper, and faint berry nuance, which emerges most clearly after a good cure.

Comparable strains point toward these same directions. Listings for Amnesia-type lines frequently emphasize citrus and tropical top notes, while purple autos from reputable vendors highlight spicy-earthy backbones alongside vivid colors. A related "Auto Purple" line is often described as spicy and earthy, and this character is commonly echoed in purple Amnesia crosses.

During late flower, the bouquet intensifies, and handling the flowers may release a bright lemon-peel snap followed by warm spice. Proper drying (around 60% relative humidity) preserves volatile monoterpenes, while a slow cure adds depth as sesquiterpenes like caryophyllene come forward. Vaporization at 175–190°C typically foregrounds the citrus layer, while combustion reveals more of the earthy spice.

Flavor

On the palate, Auto Purple Amnesia tracks closely with its aroma but adds a subtle floral-berry twist. The first impression is often lemon or sweet citrus, followed by an herbal, earthy mid-palate that hints at sandalwood and clove. Exhales can bring out pepper, lavender, and a faint blackcurrant or berry skin trailing note.

Flavor persistence is above average for an auto, especially after a 3–4 week cure. Users report that vapor profiles feel cleaner and more layered than expected from quick-finishing plants, likely due to the influence of Amnesia’s terpinolene/limonene signature. Those who prefer joints or pipes will still capture the spice and earth, but glassware and vaporizers tend to showcase citrus and floral elements.

Comparative data from related lines supports these descriptors. Amnesia Purple phenotypes are frequently listed with lemon-citrus and tropical highlights, while purple autos are documented as spicy and earthy, aligning with this strain’s amalgam. Combined, drinkable analogies range from Earl Grey with lemon peel to a light-bodied herbal liqueur with citrus oils.

Cannabinoid Profile

Auto Purple Amnesia is generally medium to medium-high in THC, with most grows clustering between 14% and 20%. This range is consistent with many modern autoflowers that blend euphoric sativa traits with quicker finishing times. Purple auto lines have been listed around 12–16% THC in some catalogs, while classic Amnesia cuts can exceed 20% THC; situating Auto Purple Amnesia near the midpoint is realistic.

CBD is typically low, often well under 1%, mirroring the high-THC/low-CBD profile common to Amnesia-family genetics. Trace cannabinoids like CBG may appear between 0.2% and 1.0% depending on phenotype and cultivation, though rare autos with elevated CBG are now appearing in the broader market. As always, cannabinoid expression is environment- and nutrition-sensitive, and harvest timing can shift the perceived potency curve.

For practical use, the chemotype delivers a fast-onset cerebral buzz with a clear functional window for many users. The moderate THC band helps mitigate the jarring edge some experience with very high-THC hazes, without stripping away the sought-after uplift. Lab testing, where available, will give the most accurate snapshot, but the expected profile aligns with a bright, low-CBD sativa-leaning hybrid tempered by soothing purple influences.

Terpene Profile

The dominant terpene ensemble often features limonene, myrcene, caryophyllene, and terpinolene. Limonene correlates with the lemon-citrus nose and can contribute to mood elevation and stress relief in anecdotal reports. Myrcene brings herbal-fruity depth and may layer in mild muscle relaxation, especially later in the session.

Caryophyllene, a sesquiterpene that can interact with CB2 receptors, contributes peppery spice and is frequently associated with anti-inflammatory potential in preclinical literature. Terpinolene adds a bright, slightly woody-floral note and is closely tied to uplifting, creative effects in many sativa-leaning cultivars. Secondary traces of ocimene, linalool, and humulene may appear, further refining floral, sweet, and woody edges.

As rough expectations, many batches will express limonene and myrcene each in the 0.2–1.0% range, caryophyllene around 0.1–0.5%, and terpinolene from 0.1–0.4%, though actual values depend heavily on phenotype, environment, and curing. Seed listings for Amnesia Purple variants flag limonene dominance, while purple auto lines often emphasize caryophyllene and myrcene, matching this strain’s dual profile. Proper post-harvest handling is critical to preserving monoterpenes; rushing the dry can cut terp content by double-digit percentages.

Experiential Effects

Users describe Auto Purple Amnesia as energizing yet centered, with creativity and focus arriving first. The initial lift often appears within 1–3 minutes when inhaled, peaks around 30–60 minutes, and trails off after 2–3 hours. This arc reflects the Amnesia lineage’s classic cerebral rise, buffered by a warm, body-calming undertone from the purple side.

Emotional tone trends toward uplifted, relaxed, and sometimes talkative, which aligns with common descriptors for Amnesia variants. Anecdotally, it pairs well with brainstorming, music, light social settings, and outdoor walks, especially in low to moderate doses. At higher doses, the sativa tilt can feel racy to those prone to anxiety, so dosing prudence helps keep the experience positive.

Taste and terpene expression can subtly shape the experience as well. Limonene-rich expressions may feel sunnier and more motivational, while myrcene-forward phenos lean relaxing and tension-releasing. Overall, the strain’s balancing act makes it a flexible daytime-to-evening option rather than a pure couch-locker or a white-knuckle rocket.

Potential Medical Uses

Given its typical chemotype, Auto Purple Amnesia may assist with low mood, stress, and mild fatigue, especially in daytime applications. Reports from Amnesia-type consumers often highlight creativity and euphoria, which can support motivation and mood rebalancing. The purple influence can add muscle relaxation and tension release, sometimes noted for post-exercise recovery or end-of-day unwinding.

Evidence bases for cannabinoids are nuanced. The National Academies (2017) concluded there is substantial evidence that cannabis is an effective treatment for chronic pain in adults and moderate evidence for improving short-term sleep outcomes in some conditions. THC-dominant profiles like this have also been associated with antiemetic effects and appetite stimulation, which can benefit select patients.

Terpenes may contribute synergistically. Caryophyllene’s CB2 activity is implicated in anti-inflammatory pathways in preclinical models, while limonene shows anxiolytic potential in animal studies. As always, medical use should be guided by local laws, clinician input, and conservative dosing, with a start-low, go-slow ramp to minimize adverse effects.

Cultivation Guide: Planning and Setup

Auto Purple Amnesia is designed for speed and simplicity, making it ideal for first-time indoor growers and seasoned cultivators alike. Most plants finish in 70–85 days from sprout, with some phenotypes wrapping closer to 63–70 days under optimized conditions. The compact structure performs well in tents and cabinets, and an 18/6 or 20/4 light cycle throughout is standard for autos.

Select pots sized 7–11 liters (2–3 gallons) for a balanced canopy and efficient wet-dry cycles. In coco or soilless blends, aim for a pH of 5.8–6.2 and an EC of 1.2–1.8 during peak growth, while soil grows prefer a pH near 6.2–6.8 with nutrient strengths guided by manufacturer feeding charts reduced by 10–20%. Good airflow and filtration help preserve terpenes and control odor; a 4-inch inline fan with a matched carbon filter can scrub tents up to ~120 cm square.

For lighting, modern full-spectrum LEDs delivering 600–900 µmol·m−2·s−1 PPFD at canopy during peak flower are effective. Target 24–30°C daytime and 20–22°C nighttime temperatures, with 60–70% RH in early veg, tapering to 50–55% in mid flower and 45–50% in late flower. Dropping night temps by 3–5°C in the final weeks can enhance purple expression without stalling growth.

Cultivation Guide: Germination to Early Veg (Days 0–14)

Germination success rates above 90% are common with fresh seed when using hydrated plug media or the paper towel method. Keep temperatures around 24–26°C and avoid over-saturation to prevent damping-off. Once cotyledons open, place seedlings under moderate light (~200–300 µmol·m−2·s−1) to encourage sturdy growth.

Autos dislike transplant shock, so many growers start seedlings in their final containers. If you transplant, do so by day 10 at the latest and handle gently to protect the taproot. Begin light feeding once the first set of true leaves fully opens; in coco, 0.4–0.6 EC with calcium-magnesium support is often sufficient.

Irrigate with small volumes around the seedling’s root zone to promote downward root exploration. Maintain RH near 65–70% and VPD in the 0.8–1.0 kPa range to support steady transpiration. By the end of week two, you should see 3–4 nodes and early side branching under consistent conditions.

Cultivation Guide: Mid Veg and Preflower (Days 15–35)

Between days 15 and 25, plants accelerate vegetative growth and set the foundation for yield. Increase light intensity to ~400–600 µmol·m−2·s−1 and feed to 0.8–1.2 EC in coco or modestly enriched soil. Keep RH at 55–65% and temperatures at 24–28°C for fast node stacking.

Low-stress training (LST) can begin once the main stem is pliable, usually around day 18–22. Gently bend and tie the apex to level the canopy and expose lower sites, avoiding high-stress topping that can stall autos. A single soft tie and strategic leaf tucking can add 10–25% more usable bud sites without extending the lifecycle.

Preflower pistils often appear by days 21–28. As stretch initiates, slightly increase potassium while avoiding excess nitrogen that can promote leafy buds and delay maturity. Expect a 1.5–2x vertical stretch from the start of preflower to the end of week five.

Cultivation Guide: Flowering (Days 36–Harvest)

By days 35–42, most plants are well into flower with visible calyx development and resin formation. Elevate PPFD to 700–900 µmol·m−2·s−1 if CO2 is ambient and to 900–1100 µmol·m−2·s−1 only if supplemental CO2 (up to ~900–1000 ppm) and extra airflow are provided. Maintain RH at 45–55% to minimize botrytis risk as buds thicken.

Nutritionally, transition to bloom formulas with a balanced NPK such as 1-2-2 or 1-3-2, keeping overall EC around 1.4–1.8 depending on medium. Calcium and magnesium support remains vital, particularly under LED lighting where Ca/Mg demands rise. Monitor runoff EC in soilless setups to avoid salt buildup; if runoff exceeds input by 300–500 µS·cm−1 consistently, a light flush can prevent lockout.

Anthocyanin expression ramps in late flower, particularly when night temps drop 3–5°C below day temps. Aroma intensifies quickly; carbon filtration and adequate negative pressure in the tent preserve household privacy and room air quality. Most phenotypes are ready between days 70 and 85 from sprout, with some earlier finishers at 63–70 days.

Cultivation Guide: Environment, Nutrition, and Training

Environmentally, autos appreciate stability. Keep day/night swings modest and avoid extreme humidity that can dampen terpenes and promote pathogens. A leaf surface temperature (LST) 1–2°C below ambient is common under LED; adjust fixture height to prevent photobleaching.

Nutrition should be moderate and consistent. Many growers find that 70–85% of the manufacturer’s feed chart hits the sweet spot for autos, with incremental increases only if leaves are pale and growth is slow. Aim for a pH of 5.8–6.2 in coco and 6.2–6.8 in soil; correct drifts promptly to avoid micronutrient issues.

Training is best kept gentle: LST, leaf tucking, and selective defoliation of large fan leaves blocking critical bud sites. Avoid topping past day 20–22 to prevent delays in autos’ fixed lifecycle. A supportive trellis or plant yo-yos can stabilize heavy colas late in bloom without stressing stems.

Cultivation Guide: Outdoors and Greenhouse

Outdoors, Auto Purple Amnesia thrives in 18–28°C conditions with ample sun and low prolonged humidity. In temperate zones, two to three sequential runs per season are feasible due to the 9–12 week seed-to-harvest window. Planting from late spring through midsummer maximizes radiation and reduces mold pressure.

Expect 50–150 g per plant outdoors in 11–20 liter containers when grown in full sun with quality soil and regular irrigation. In the ground with amended beds, yields can surpass container runs due to unrestricted root space and soil-buffered nutrition. Greenhouses extend the season, buffer against rain, and improve terp retention by enabling slow, controlled drying on-plant as temperatures taper.

For color expression, late-season swings and cool nights help draw out purple hues. However, sustained lows below 12–14°C can slow metabolism and stall finishing, so plan for frost protection where needed. Integrated pest management—beneficial insects, sticky traps, and regular scouting—keeps common outdoor threats like aphids and caterpillars in check.

Harvest, Drying, and Curing

Harvest timing benefits from a multi-signal approach. Aim for milky trichomes with 5–15% amber if you want a balanced effect; harvest slightly earlier for a brisker head and slightly later for a heavier body. Pistils turning from white to orange-brown and calyxes swelling are additional ripeness indicators.

Drying should target the classic 60/60 guideline: ~60°F/15.5°C and 60% RH for 10–14 days, with gentle airflow and darkness to protect cannabinoids and terpenes. Overly warm or dry rooms can strip monoterpenes and lead to harsh smoke; aim for a 1–2% moisture drop per day. Stems should bend and nearly snap when ready to jar.

Curing proceeds in airtight containers at 58–62% RH for 3–6 weeks, with daily burping the first week and tapering thereafter. Water activity (aw) between 0.55 and 0.65 is ideal for stability and flavor development. Most citrus-forward expressions peak in aroma by week 4 of cure, while earthy-spicy notes continue to deepen into week 6 and beyond.

Yield Expectations and Optimization

Indoors, Auto Purple Amnesia typically returns 350–500 g·m−2 under efficient LEDs, with dialed-in grows occasionally pushing higher. Single plants in 7–11 liter pots often produce 40–120 g, driven by genotype, environment, and training. Outdoors, 50–150 g per plant is a realistic band in containers, with in-ground runs exceeding that in favorable climates.

To optimize yield, focus on even canopies and consistent VPD management. Maintain PPFD in the 700–900 µmol·m−2·s−1 range during peak bloom and ensure CO2 at ambient or slightly enriched levels if increasing intensity. Light LST to distribute tops, a balanced bloom nutrition profile, and avoidance of deep nutrient swings are the big levers.

Quality optimizations include moderate night temp drops for color, careful drying to protect terpenes, and a full 3–6 week cure. Small improvements at each stage compound; preserving 10% more terp content during dry and cure can make the difference between good and exceptional. Keep meticulous notes each run to identify which environmental tweaks correlate with potency and aroma improvements.

Common Issues, IPM, and Troubleshooting

The most common issues in autos are overfeeding early, overwatering, and heavy-handed training that slows growth. If leaves darken and claw, reduce nitrogen; if interveinal chlorosis appears in coco, check pH and increase cal-mag slightly. Keep wet-dry cycles healthy—pots should feel light before re-watering to maintain oxygen at the root zone.

Integrated Pest Management (IPM) begins with prevention: clean spaces, quarantined clones or tools, and sticky traps for early detection. Beneficial insects like Encarsia formosa for whiteflies and Phytoseiulus persimilis for spider mites can be deployed proactively, particularly in greenhouses. Neem-alternative soaps and horticultural oils are best used in veg or very early flower to avoid residue on buds.

Bud rot (Botrytis) risk increases in dense, colorful colas under high humidity. Keep RH under 55% in mid-late bloom, ensure strong but indirect airflow around flowers, and defoliate sparingly to improve penetration. If localized rot appears, remove it immediately with sterilized tools and increase environmental controls to stop spread.

Comparative Context and Live Info Integration

Traits reported for related cultivars help triangulate expectations for Auto Purple Amnesia. Amnesia lines are widely described as uplifting, creative, and euphoric with high THC and low CBD, which matches the cerebral lift many users feel here. Amnesia Purple phenotypes are often listed with heavy yields, citrus-lemon-tropical flavors, and limonene-forward terpene dominance, consistent with this strain’s aroma.

Purple autos from reputable seed vendors frequently highlight sweet-spicy-earthy flavors and relaxing body effects in the 12–16% THC range. This aligns with Auto Purple Amnesia’s likely THC bracket in the mid-to-high teens, occasionally cresting around 20% in optimized grows. In the broader auto market, compact, resin-packed buds and fast-hitting effects are repeatedly emphasized by breeders showcasing their best-selling autos, underscoring what growers can aim for here.

Taken together, these live market notes dovetail with Short Stuff Seedbank’s ruderalis/indica/sativa heritage claim. Expect a citrus-spice nose, a clear creative onset, and a physically relaxing taper—delivered in a colorful, compact plant that finishes quickly. The purple colorway is phenotype-dependent, but cool nights in late flower substantially increase your odds of vivid hues.

Responsible Use, Dosing, and Safety

With THC commonly in the mid-teens to around 20%, start with low doses, especially for daytime tasks. Inhaled doses of 1–2 puffs, then wait 10–15 minutes, help gauge the uplift without overshooting into raciness. For edibles, begin at 1–2.5 mg THC and titrate upward on separate days.

Those prone to anxiety may prefer lower doses or pairing with CBD, though CBD content in this strain is typically low. Stay hydrated and avoid mixing with alcohol, which can magnify impairment and dizziness. Never drive or operate machinery under the influence; effects can persist for several hours even after the perceived peak.

If you experience discomfort such as racing thoughts or palpitations, take a break, find a calm environment, and breathe steadily. Black peppercorn aroma (caryophyllene) is a popular folk remedy some find grounding, though evidence is anecdotal. Consult a clinician if using cannabis medically, particularly if you have cardiovascular, psychiatric, or drug-interaction considerations.

Final Notes and Strain Positioning

Auto Purple Amnesia earns its place as a high-utility autoflower that brings color, citrus-spice character, and a balanced psychoactive profile into a tight timeline. It slots neatly between classic hazes and heavy indica autos, giving growers a flexible cultivar that is as photogenic as it is practical. In small tents or balcony planters, it delivers efficient yields, bright aromas, and approachable potency.

For enthusiasts who value both vibes and visuals, the strain’s lemon-forward inhale, peppery-earth exhale, and plum-toned buds tick many boxes. Its heritage—ruderalis/indica/sativa, bred by Short Stuff Seedbank—shows in the way it completes a full, flavorful cycle without photoperiod management. With careful drying and a slow cure, Auto Purple Amnesia reliably graduates from quick-grow auto to connoisseur-grade jar.

Whether you are seeking a compact sativa-leaning daily driver or a colorful addition to a diversified garden, this cultivar provides a data-backed, experience-tested option. Keep conditions stable, train gently, and let the colors come in late. The payoff is a citrus-sparked, spice-anchored flower that feels as good to grow as it does to share.

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