Cannabis Cultivation

Our team of experts have assessed hundreds of cannabis cultivation facilities ranging from small-scale domestic set-ups to the conversion of industrial units containing thousands of plants. We understand the complexities of producing cannabis and are frequently called upon to provide expert evidence on cannabis growing facilities and medical use of cannabis.

In recent years more and more cannabis users have turned to growing the drug for a wide variety of reasons, including those who use cannabis to alleviate medical conditions. For many users it may simply to be to reduce the cost of purchasing the drug and to avoid mixing with unscrupulous suppliers who often supply cannabis that is of poor quality and may have been developed using harmful pesticides or chemicals.

For those people who use cannabis to alleviate the discomforting symptoms of a wide variety of medical conditions then the market has evolved significantly with the emergence of cannabis plant strains bred specifically for medical users. There is growing awareness of the therapeutic effects of cannabis and many strains of cannabis are now developed with lower levels of THC but higher proportions of cannabidiol (CBD). Changes in legislation in many countries has seen wider access to cannabis for both medical and recreational users of the drug. In the UK cannabis remains a controlled drug under the Misuse of Drugs enactment making it unlawful to possess.

We are one of the leading UK experts on cannabis cultivation and cannabis production cases having assessed hundreds of cases in recent years ranging from a handful of plants grown in small cupboards to large scale industrial units or houses extensively modified and containing hundreds or even thousands of plants. It never fails to amaze us that proper challenges to inflated estimates of yield or value are not put forward at an early stage in such cases, particularly when there is the potential for confiscation proceedings under the Proceeds of Crime Act to follow.

Personal Grower or Commercial Supplier?

Perhaps the biggest challenge that is faced when considering a cannabis growing facility is whether this was simply an attempt to grow enough cannabis for a single user or production of the drug where the intention was for some distribution. For these purposes even distribution amongst friends whether for profit or not represents supply and is viewed far more seriously in law.

The distinction between the two is often blurred and much will be left to the police and the Crown Prosecution Service to decide the appropriate charge. There appears to be little awareness of the practical difficulties faced when producing cannabis and similarly little understanding of the motivation of some users who suffer from medical conditions for which conventional medicines produce little effect or the negative effects outweigh the intended benefits.

For the cultivator of cannabis who is deemed to have grown the drug on a commercial basis rather than simply for their own use then the penalty is almost inevitably a custodial sentence. A conviction at this level may result in an investigation into assets and the potential benefit gained under the Proceeds of Crime Act (POCA). POCA allows the court to consider what financial benefit has been achieved by somebody convicted of producing cannabis, even if it was simply for personal use and to seek repayment.

Our evidence in borderline cases often highlights practical issues that are overlooked. Projected yields that are inflated may be reduced. The health of plants or the viability of immature plants may be identified. Was the capacity of the growing space capable of maintaining the plants discovered to maturity? Single cannabis plants are often attributed a value of £840 in criminal trials by police officers valuing the plants, even if the plant is immature.

Where proceedings are instigated under POCA estimates of benefit are often based upon the potential number of crops that the grower may have previously produced and the potential value of these crops. The grower may then find that the court seeks to strip them of the assessed benefits derived from the offence. The potential benefit of even fairly modest grows when assessed over an extended period can run into thousands of pounds. It is our experience that such estimates are often inaccurate and convicted cannabis growers are forced to pay back excessive amounts when yields and drug valuations are not challenged.

How is a cannabis cultivation scene assessed?

In many cases a sample number of plants are seized as being representative. The remaining plants are often destroyed immediately along with all equipment. Where there is the potential that the growing facility could be commercial in nature or the grower disputes that they are cannabis the representative plants will be analysed. Previously such analysis would take place at a laboratory by a qualified Forensic Scientist but in recent years police officers have begun calculating plants yields.

Current yield estimates provided by many police forces range from 28 to 84 grams per plant. This is not restricted to mature plants however and will commonly include immature plants as well as unrooted cuttings which are considered as viable plants from which a yield is calculated. Some police officers will consider quantities of leaf and flowering top material to be a usable product which they will value. Our experience has shown that often waste leaf material is included in the valuation evidence and valued at a similar level to that achieved by flowering top material.

If the cannabis plants are flowering and in the latter stages of growth then the yield from the representative plants is weighed and multiplied by the total number of plants.

e.g. Single representative plant yields 50 grams then based upon the 10 plants recovered from the address yielding a similar amount the potential yield would be 500 grams. A valuation is then applied to the potential yield by the police typically based upon a price of £10 to £15 per gram. The potential value of this grow would range from £5,000 to £7,500.

But what if the plants aren’t flowering, how will they be valued then? Well in real terms plants at that stage of growth are effectively worthless but police officers will attempt to predict the potential yield based upon police data of cannabis plants and average yields. There can be considerable difference in the estimates provided which have increased considerably in recent years. Officers frequently suggest that yields of 84 grams per plant are typical with little consideration of the growing facilities such as available lighting or space.

If ten immature plants are discovered then the estimated yield could be as high as 840 grams. At a street value of £10 to £15 per gram then even a modest grow is considered to be potentially worth £12,600. If we then factor in the potential value of the leaf material, often valued at £5 per gram then it is easy to see why even a modest growing facility can be considered to be commercial.

As the vast majority of cannabis growers now utilise a method based loosely on the “Sea of Green” then it is common for past and future crops to be included in the valuation. Cuttings are commonly valued as mature plants despite being at an immature stage of growth and little consideration is given to potential failure rates. The grower may cultivate 20 cuttings with an expected attrition rate of 50 % leaving ten viable plants to replenish the more mature crop. If discovered though then for the purposes of yield estimates and valuations for court proceedings the yield is likely to be based upon 30 plants with little consideration of the age of the plant. In such circumstances a simple 10 plant grow and 20 cuttings can result in a potential yield of 2,520 grams with an estimated value of over £37,000.

Been arrested? We offer expert evidence services across the UK. If you dispute the police evidence then ask your solicitor to consider an expert report and to contact us.

If you need a solicitor we have a nationwide database of solicitors with experience in cannabis cultivation cases – please call us and we can provide details of a solicitor in your area.

Sign up to our newsletter

Subscribe to our newsletter