Homegrown's place in the UK cannabis
market
Whilst the plethora of "Grow your
own" guides, the ready availability of a wide range
cannabis seeds and growing equipment through the Internet
and other outlets and the publishing success of regular
magazines for the cannabis user would suggest widespread
interest in home cultivation, information on its extent
is scarce. The little information we do have comes from
the regular surveys of cannabis users carried out by
the Independent Drug Monitoring Unit (IDMU). Since 1984,
the IDMU has been distributing questionnaires to regular
cannabis users at popular music festivals and have provided
a valuable picture of drug consumption patterns, prices
and markets in the UK. Although lacking the finer points
of sample representativeness, these regular surveys
are generally viewed as a reliable barometer of changes
in the UK drug market.
The findings from their most recently
published survey for 2001 found that domestically-produced
cannabis was now taking a dominating role in the UK
cannabis market and made up nearly half of UK cannabis
consumption. Homegrown had now overtaken Moroccan (soap-bar)
resin, hitherto the major product in the cannabis market,
for the first time. With the 1984 survey reporting just
10% of the respondents using homegrown, the growth in
the availability of UK-grown cannabis is apparent.
Cannabis cultivation systems in the UK
vary from one light in a cupboard, up to industrial
units holding thousands of plants. The vast majority
of growers now use high intensity lighting, and hydroponic
nutrients and cultivation vessels tend to be the norm
(although higher potencies are generally found from
organic-grown plants), although methods vary, most growers
will have separate areas for growth and flowering, allowing
simultaneous propagation of cuttings from mother
plants, and growing these to the desired height
(with 18-24 hours light) before transferring to the
flowering zone (12 hour light/dark cycle). Outdoor cultivation
is becoming much rarer, as the plant is now more easily
recognised by members of the public.
Growers may cultivate a few large plants,
or many small plants, with the yield from individual
plants ranging from under one gram to 100 grams or more.
The number of plants is therefore an unreliable guide
to the potential yield or scale of cultivation in a
particular system. Smaller plants may be harvested more
quickly although, broadly speaking, the potential yield
of a system is a function of the available space, the
intensity of the lighting, and the variety grown (short
bushy plants obviously yield more than tall spindly
plants).
Growers with a single cultivation chamber
cannot sustain continuous production, and would take
4-6 months to harvest a crop. With efficient use of
two growing zones, it is possible to reduce the interval
between successive harvests to 2-3 months.
A two-chamber system with 2-3 lights,
and a flowering area of 1-2m2 can sustain
personal consumption for a moderate to heavy user-users
who grow cannabis tend to smoke more than those who
have to buy it. However, users who grow cannabis are
also roughly twice as likely to be arrested for cannabis
offences than those who have never grown cannabis plants.
The majority of cannabis growers grow
the plant in indoor cultivation systems. Casual
growers will often plant a few seeds found in imported
bush and grow a few plants on windowsills or balconies,
although an increasing number of respondents are growing
cannabis from a combination of pedigree seeds
and cuttings, using hydroponic systems and high-intensity
horticultural lighting.
Between 1994 and 2000, the proportion
of growers using hydroponic cultivation systems trebled
from 6% to 19%, and use of high power lighting increased
from 17% to 41% while natural light usage fell from
77% to 56%. Over the same period the proportion of growers
using seeds from deals of imported cannabis bush fell
from 49% to 21% (probably reflecting reduced market
availability), while the proportion using pedigree
seeds rose from 35% to 57%.
In 2000, growers tended to use more lights,
with an average of 4.5 lights with an average total
wattage of 1067W, compared to just under 2 lights with
total wattage of 421W in 1999.
This increasing high-tech trend was also
reflected in the quantity grown, in 1998 growers produced
an average of 12 plants with an total yield of 189g,
in 2000 the figure was 23 plants with average yield
of 462g.
Growers tend to be heavier users, with
the average non-grower smoking 2.6 reefers or pipes
a day and using 21g per month, compared to growers having
6.3 smokes per day and using 30g per month.
Home Office Seizures: Arrests for
cannabis cultivation peaked in the mid 1990s, when many
police forces were actively targeting growing operations.
Since 1995 the number of seizures has fallen substantially,
suggesting domestic cannabis cultivation to have fallen
down the list of police priorities, although recent
seizures have involved larger numbers of plants, with
a higher proportion involving commercial-scale operations.
|
Year
|
1990
|
1991
|
1992
|
1993
|
1994
|
1995
|
1996
|
1997
|
1998
|
1999
|
2000
|
|
Total
seizures
|
818
|
1045
|
1910
|
4124
|
5684
|
6128
|
4936
|
3791
|
2832
|
2288
|
2020
|
|
Total
plants
|
34031
|
8896
|
11839
|
71234
|
57865
|
94382
|
116301
|
115057
|
123043
|
55810
|
47811
|
|
Average
plants
|
42
|
9
|
6
|
17
|
10
|
15
|
24
|
30
|
43
|
24
|
24
|
