There is no Spanish legal provision that expressly authorises growing cannabis, but nor is there any maximum or minimum number of plants established for home cultivation in a private residence. This means that any specific figure you read in forums or videos — "you can have up to X plants" — is, at best, an approximation based on prior case law, not a rule currently in force.

Across a series of rulings, the Spanish Supreme Court has defined a set of requirements that guide — without guaranteeing — a finding of personal use: identified, habitual consumers; a closed, private location; a moderate quantity proportional to expected consumption; consumption within that closed circle; and a total absence of profit motive. None of these requirements is decisive on its own; they are assessed together.

A Spanish Supreme Court ruling of 25 July 2021 clarified that these case-law requirements should not be applied as a checklist to tick off, but as indicators that help build an inference judgment about the grower's actual intent, always assessing the specific case as a whole. This explains why two apparently similar cases can be resolved differently depending on what other factors come into play.

None of these cases was decided on the plant count alone: in every one, the deciding factor was the combined assessment of other elements — no signs of selling, the grower's profile as a habitual consumer, growing conditions consistent with personal or club use, and the absence of elements typical of a commercial operation (see section 6). The disparity between these numbers — from 58 to as many as 222 plants acquitted — is precisely the proof that there is no fixed threshold, only a case-by-case assessment.

• Individualised or split doses — presenting the product already divided into small quantities typical of sales, rather than in its natural harvested form.
• Weighing or cutting equipment — precision scales, individual dosing bags, or other materials associated with preparing product for sale.
• Cash in small denominations — banknotes and coins of small values, consistent with proceeds from repeated transactions.
• Surveillance findings or third-party traffic — frequent visits from people not identified as part of a closed, stable group.
• A quantity disproportionate to the proven consumption pattern — output far exceeding what the person (or closed group) would reasonably consume over the relevant period.

Proving habitual-consumer status, one of the five requirements described in section 3, is rarely settled by a simple statement from the grower. In judicial practice, this point is often supported by expert toxicology reports, testimony from people close to the individual, medical records related to consumption, or even a history of prior interventions for possession for personal use that reinforce a consistent, sustained consumption pattern over time.

The Non-Jurisdictional Plenary Agreement of the Second Chamber of the Spanish Supreme Court, of 19 October 2001, set as an indicative reference that possession of up to 100 grams of marijuana or 25 grams of hashish, intended for personal use, should not be treated as a criminal offence. It's important to understand that this reference was established with possession of already-harvested product in mind, not a number of plants under cultivation — translating that threshold directly into a number of plants is an oversimplification that doesn't reflect how courts actually reason.

For shared personal use to apply, case law requires a closed, stable group of identified consumers (with no open access to the public), all of whom must be adults, a total absence of profit motive in how the group operates, a proportional contribution from each member toward expected consumption, production or acquisition limited strictly to that specific group's needs, and consumption taking place in a private location not visible to the public.

The cases covered in section 4 — from an acquittal over 58 plants in Tenerife to one over 222 in Lugo — don't reflect a neat, linear "more plants, more risk" scale, but rather a genuine disparity of criteria among different Spanish courts and provincial appellate courts (Audiencias Provinciales). This disparity has been explicitly flagged by outlets specialising in coverage of these cases, which speak openly about differences in how judges apply the same case-law doctrine to similar facts.

Growing indoors, in a grow tent or a fitted-out room, tends to favour the "closed, non-visible location" requirement described in section 3, precisely because it naturally limits access to and public exposure of the grow. This doesn't automatically make it legal, but it does make it easier to prove one of the elements that case law weighs favourably compared with an exposed grow.

Many of the circumstances that later allow a judge to find personal use — or, conversely, to lean toward a trafficking classification — are documented precisely during this initial phase: how the product is presented at the time of the search, what's found alongside the plants, and what statements are made. This means that how that first contact with the authorities is handled — without lying, but also without volunteering unnecessary information without prior legal advice — can shape how the case is built from the outset.

• Assuming there's a safe "magic number" — as section 4 shows, even high numbers have been acquitted and lower numbers convicted, depending on the overall circumstances.
• Sharing or giving away product outside a closed, stable group — this can seriously undermine the personal-use or shared-consumption argument.
• Keeping notes, lists or messages that look like a sales ledger — even without any real intent to sell, this kind of material can be interpreted as a sign during a search.
• Growing visibly from a public road or communal areas — lack of privacy is, on its own, one of the elements case law weighs negatively.

This article is for informational and educational purposes only, and summarises general case-law criteria in force in Spain at the time of publication. It does not constitute individualised legal advice. Legislation and case law can change, and each case is decided on its own specific circumstances. For any real situation, always consult a specialist criminal defence lawyer with expertise in offences against public health.