Sativa seeds come with more vocabulary around them than any other kind of cannabis seed, and most of it means one thing to a botanist, something else to a breeder and a third to the person standing in front of the pack. The failed sativa grow nearly always traces back to a word that was understood in the wrong one of those senses: a flowering time read as a fixed number, a “sativa-dominant” label read as a description of character, a landrace chosen as if it were a tent-bred hybrid. The entries below are written with the range at https://hazesativaseeds.com to hand as reference, since it runs strongly to the classic end of the category and that is where the words matter most; the meanings though apply to any sativa seed from any shop. They are in no special order, since not one of them is sense on its own without the rest.
Haze
In its first sense a particular line of plants put together in 1970s California from Mexican, Thai and South Indian landraces, and then kept and refined in the Netherlands. The Haze grows tall, fills out openly, flowers for twelve to to sixteen weeks and carries a scent of spice, citrus and something metallic that no line exactly reproduces.
In its looser sense “Haze” is whatever cross which carries a share of that family, which today is a great many of the sativa-leaning catalogue. A listing that reads “Haze” without parents may be eighty percent original old family or one sixteenth of it, and the flowering character follows the fraction, not the name. The useful question is never “is it a Haze” but “how much, and via which parent”.
Sativa-dominant (the label)
A catalogue category and not a botanical one. It usually indicates that the larger share of a hybrid’s parents were described as sativa by whoever drafted the listing, which occasionally means nothing more than a certain the flowers are airier or the aroma sharper than the same breeder’s indica-labelled lines.
The effect people associate with the word, clear-headed instead of sedating, is governed more by terpene chemistry and by THC content than it is by the sativa fraction, and plenty of “sativa-dominant” hybrids deliver a heavy sleepy effect while plenty of the opposite stock do exactly the reverse. For a buyer the label is worth something as a loose guide to growth habit, flowering time and stretch; for a guide to how it feels it is close to useless without the terpene notes.
Terpinolene
A terpene found in large proportion in many classic sativa strains and responsible for most of what people mean as a “sativa” aroma: green, woody, citrus and faintly sweet all at once. It is fragile, driven off easily through fast drying, and terpinolene degrades faster in the cure than the earthier terpenes that lead indica-leaning lines.
For a seed buyer the word earns two things. Where a listing lists terpinolene as the lead terpene, the strain probably has substantial old-sativa genetics regardless of what the percentage claims. And when the grower wants that profile to still be there by the jar, the drying is going to be slow and cool; a warm drying room flattens a terpinolene line to something that tastes of very little and leaves nothing of what the pack described.
Foxtailing (and when it is not a fault)
The habit of some flowers to grow new calyx growth on top of old ones, giving spired, irregular buds instead of dense ones. In the majority of tent-bred lines it is a heat response, typically from light that is too close or a room too high, and the advice is to correct the cause.
In a good number of sativas, especially Thai and certain Haze lines, it is genetic and will occur under a perfect room. A new sativa grower often wastes a month chasing a fault that is there, lowering lights and heat and delaying an already long plant further. The breeder rarely says which kind to expect; the lineage generally does.
Intersex tendency
The production of male flowers on a female plant, usually late in flower and often in response to stress. Every cannabis line has some capacity for it; long-flowering plants show it more often, and the reason is one plain one: sixteen weeks of flower is fourteen weeks of exposure for a timer leak, a heat spike or a late watering to trigger it off, and a old that has already gone beyond its natural end often produces a few desperate pollen sacs on its own as a final attempt to set seed.
None of these makes a sativa strain unstable by nature; it makes the room’s discipline count for longer. A sealed tents, stable temperatures and harvesting the moment the plant is ready rather than a weeks after take away the greater part of the risk. A listing which mentions the breeder screens parents for hermaphrodite traits is worth worth hearing for a sativa than for any other category.
Stretch (the doubling)
The burst of upward growth that comes after the change to flowering. Most tent-bred plants add around half their height again; sativas commonly double, and a few landrace lines go further. The stretch lasts two to five weeks and will not be halted once it has started, merely redirected by training.
In practical terms, the stretch multiplier is the number worth reading before deciding when to flip. A sativa flipped at sixty centimetres in a two-metre tent is at the lamp before week four of flower; one flipped at thirty centimetres centimetres has room. Growers moving over from indica strains nearly always switch far too late the first time, and the consequence is visible on the ceiling of the tent.
Landrace versus heirloom
A population of plants adapted over generations to a particular region by the local climate and growers together, rather than by deliberate selection. Colombian, Thai, Congolese and Mexican stock are the sativa cases. A landrace is variable, not a single plant: within a pack the flowering times, flowering times and aromas spread widely than in a tent-bred line, and that spread is the point of keeping one.
The trap is buying a landrace like a modern hybrid. It carries traits that made sense in an equatorial field, including height no tent can hold and a flowering clock set to a daylength the majority of growers cannot offer. “Heirloom” on a listing usually means a landrace that has been reproduced away from its origin for some generations, often with a degree of selection towards indoor conditions; it is nearer to manageable but still far from uniform. A seller offering “landrace” without an collection point and a generation count is applying the word as a flavour, and the seeds should be judged accordingly.
Equatorial (the twelve-hour problem)
Describes lines from regions in which daylength hardly changes through the year, and where the plant never evolved a strong reaction to changing days. These plants often start flowering slowly under a standard twelve-hour light cycle, since twelve hours is, for them, an unremarkable day rather than a signal.
The working fix, passed down between sativa growers for decades, is to cut the light further: eleven hours, occasionally ten, especially in the final weeks. It costs some little yield and gains an earlier decisive finish. A listing that uses “equatorial” is telling you this with one word, and a grower who reads it as mere geography has missed the point inside it.
Flowering time (and what it is counted from)
The figure of weeks from the start of flowering and harvest, which is the single most frequently misunderstood figure on a sativa pack. With photoperiod seed it is measured from the day the light drops to twelve hours, not from germination, so a “fourteen-week” sativa grown with an eight-week vegetative period is a twenty-two-week plant. Breeders additionally quote the optimistic end of a spread, because the other end moves less seed.
Long-flowering lines take anywhere from ten weeks to well over twenty, and the slowest strain in the Haze Sativa Seeds range comes in at around 16 weeks after the flip. The catalogue can be sorted by that figure, which is a reasonable first step for a room with a tight timetable. A grower who allows four weeks on top of whatever the pack says is rarely caught out.
Latitude (outdoor sativas)
The single number that decides if a sativa can ripen outdoors, and a number no pack states. Equatorial lines require a run of shortening days to continue long enough for the plant to ripen; at northern latitudes the frost comes before that, and the grower harvests a half-finished plant in the end of October or watches it rot in November. The closer south, within the northern hemisphere, the later the season runs, and Mediterranean and low-latitude gardens can finish plants that temperate gardens never will.
The practical reading for a seed pack: an “outdoor” sativa finishing date is stated for the breeder’s home latitude, usually a point in southern Europe or the western United States, and each degree further north of it moves the finish back into the weather. A grower north of roughly the fiftieth parallel who wants a long-flowering sativa in the garden is shopping for a sativa autoflower or a greenhouse, and not a better summer.