How to Grow Cannabis: A Step-by-Step Home Grower's Guide

Cannabis cultivation laws vary by country and region and change frequently. This guide is educational. Before growing, verify current laws for your specific jurisdiction. Azarius does not provide legal advice.

This guide is written for adults aged 18 and over. Growing cannabis is a horticultural project — the sections below cover plant biology, equipment, and technique, not consumption, effects, or pharmacology. For anything cannabinoid-related, head to the cannabinoids hub.

Before you start: the legal bit and the honest bit

Home cultivation legality is all over the place in Europe. As of Q2 2026, Germany's Cannabisgesetz (CanG, in force since 1 April 2024) allows adults to grow up to three plants at home for personal use (Bundesministerium für Gesundheit, 2024). Malta permits up to four plants per household under Act No. LXVI of 2021. The Netherlands still treats home cultivation as a minor offence if plants are spotted and reported, despite its famously relaxed retail culture (EUDA, 2024). Most other EU countries prohibit it outright or allow only cannabis seeds as collectors' items. Verify your specific jurisdiction before germinating anything.

AZARIUS · Before you start: the legal bit and the honest bit

Now the honest bit: a first grow tends to produce less than you think and cost more than you planned. That's fine. The point of the first run is to learn your space — airflow dead zones, your tap water's pH, how your genetics actually behave. Plan for the second grow while you're running the first.

Step 1: Pick your genetics

Before lights, tents, or nutrients, pick the seed. This decision shapes everything else — cycle length, plant size, training options, even your electricity bill.

AZARIUS · Step 1: Pick your genetics

Feminised photoperiod seeds produce effectively 100% female plants and flower when you switch the light cycle from 18/6 to 12/12. Total cycle: roughly 12–16 weeks seed-to-harvest, depending on genetics and veg time. These are the workhorse of European home growing — Dutch Passion's Blueberry, Paradise Seeds Wappa, Royal Queen Seeds Northern Light are all solid beginner picks with breeder documentation you can actually trust.

Autoflowering seeds flower based on age, not light cycle, usually 9–11 weeks from germination to harvest. You keep lights on 18/6 or 20/4 the whole time. Smaller plants, forgiving of light leaks, but you can't clone them and training options are limited because there's no veg-to-flower switch. Good for short Northern European summers and small tents. Ministry of Cannabis Auto Mandarin Haze and Royal Queen Seeds Quick One are reliable autos.

Regular seeds produce roughly 50/50 males to females. Only worth it if you plan to breed. For a harvest grow, go feminised.

Ignore THC percentages on the seed packet for cultivation planning. They tell you little about how the plant grows, how much it stretches, or how it behaves in your tent. Read the breeder's flowering time, stretch factor, and height notes instead.

Step 2: Build your space

For indoor growing, a dedicated tent is non-negotiable. It gives you control over light, humidity, temperature, and smell. Minimum viable setup for 2–4 plants:

AZARIUS · Step 2: Build your space

• Tent: 80×80×180cm fits 2–4 plants comfortably. 120×120 if you want 4 trained plants with space to work.
• Light: A modern LED board of 150–250W actual draw covers an 80×80 for both veg and flower. Aim for 400–600 PPFD during veg, 600–1,000 PPFD during flower. HPS still works but runs hotter and eats more electricity.
• Extraction: An inline fan rated for roughly 4× your tent volume per minute, paired with a carbon filter. For an 80×80×180 tent (~1.15m³), a fan moving 180–250 m³/h is the sweet spot. The carbon filter is not optional — it handles the smell that your neighbours and landlord will otherwise notice.
• Circulation fan: A small clip-on oscillating fan inside the tent. Stagnant air kills plants.
• Thermometer/hygrometer: Ideally one that logs min/max. You need to know what your tent does at 3am, not just when you check it.

Target environment: 22–26°C lights on, 18–22°C lights off, with VPD around 0.8–1.1 kPa in veg and 1.0–1.5 kPa in flower. VPD (vapour pressure deficit) is the unified humidity+temperature metric; any free VPD calculator app does the maths.

Step 3: Choose your medium

Soil, coco coir, and hydroponics all work. They are not interchangeable.

AZARIUS · Step 3: Choose your medium

Soil is the most forgiving. A quality pre-amended organic soil (BioBizz All-Mix, Plagron Light-Mix if you want to feed earlier) holds water longer, buffers pH mistakes, and lets beginners water every 2–3 days without much fuss. Target pH 6.0–6.8 at the root zone.

Coco coir is inert — you feed every watering. Faster growth than soil, more control, but less room for error. Target pH 5.8–6.2, feed with coco-specific nutrients (CANNA Coco A+B, House & Garden Cocos A+B). Plants in coco dry out fast — daily watering in late flower is normal.

Hydroponics (DWC, RDWC, ebb-and-flow) is the fastest-growing, highest-yielding, and least forgiving option. pH swings can kill a plant in 48 hours. EC management matters. Not a first-grow medium unless you enjoy reading charts.

Pot size matters. In soil or coco, photoperiod plants need 15–25L final pots for a full cycle. Autoflowers do well in 11–15L fabric pots — and plant them directly in the final pot, because autos hate transplant stress.

Step 4: Germinate and seedling care

Germinate on a damp paper towel between two plates at around 22–24°C. Most seeds crack within 24–72 hours. As soon as the taproot is 3–5mm long, plant it 10–15mm deep in pre-moistened medium, taproot pointing down.

AZARIUS · Step 4: Germinate and seedling care

For the first 10–14 days, seedlings want:

• Humidity 65–75% (a humidity dome helps)
• Temperature 22–25°C
• Light at reduced intensity — 200–300 PPFD, roughly 30–40% on a dimmable LED
• No nutrients. The cotyledons feed the plant for the first 1–2 weeks, and pre-amended soil has enough to carry seedlings to week 3.

Water sparingly. More seedlings die from overwatering than anything else. Let the top 2cm of medium dry before watering again.

Step 5: Vegetative growth

Veg is where you build the plant's structure. Photoperiod plants stay in veg on 18/6 for as long as you want — typically 3–6 weeks from seedling stage. Autoflowers veg on the same schedule but you don't control when they flip; they just do, usually around week 3–4.

AZARIUS · Step 5: Vegetative growth

Feeding during veg is nitrogen-heavy. An N-P-K ratio around 3-1-2 is typical. Start at roughly 25% of bottle-label strength and work up based on plant response. Signs of overfeeding: claw-shaped leaf tips, dark green foliage, crispy burned tips. Signs of underfeeding: pale lower leaves, yellowing from the bottom up. EC target in coco/hydro during veg: 1.2–1.8 mS/cm.

Training starts in week 2–3 of veg. Options:

• Low-stress training (LST): Tie main stem and branches sideways to flatten the canopy. Low risk, big payoff. Do this on every grow.
• Topping: Cut the main stem above the 4th or 5th node. Plant splits into two main colas. Adds 7–10 days of recovery.
• FIMing: Pinch out ~75% of the top growth tip. Produces 4 new tops instead of 2, less predictable than topping.
• SCROG (screen of green): Horizontal net at canopy height, weave branches through. Best technique for maximising yield per watt in small tents.

Don't train autoflowers aggressively — they don't have time to recover. LST only, and gently.

Step 6: Flowering

For photoperiod plants, flip lights to 12/12. For autoflowers, the plant flips itself. Either way, the next 8–11 weeks decide your harvest.

AZARIUS · Step 6: Flowering

The stretch: Weeks 1–3 of flower. Plants can double or triple in height. Finish LST and defoliation before the stretch ends — after week 3, handling the plant is risky.

Feeding shifts to a bloom nutrient: lower nitrogen, higher phosphorus and potassium, roughly 1-3-2 ratio. EC in coco/hydro climbs to 1.8–2.4 mS/cm during peak flower. Growers in soil with pre-amended bloom mixes can get away with water-only for weeks, depending on the soil.

Humidity drops as flower progresses. Target 50–55% RH by weeks 4–5, 40–50% in the final weeks. High humidity on dense, wet buds is how you get botrytis (bud rot) — and bud rot in a crowded tent can take out half a crop in 72 hours.

IPM rule: no systemic pesticides, ever. No neem oil past week 3 of flower. If you get spider mites or thrips late in flower, options narrow to mechanical removal, predator insects, or accepting some damage. A clean grow room, sealed tent, and no plants-from-outside rule prevent 90% of pest problems.

Step 7: Harvest, dry, cure

Harvest timing is decided by trichomes, not by the breeder's "9 weeks" claim. Pick up a jeweller's loupe (30×–60×) or USB microscope and check the trichomes on the buds, not the sugar leaves. Clear trichomes = not ready. Cloudy = peak. Amber = past peak (some growers like 10–20% amber for a heavier effect — but that's consumption territory, not cultivation).

AZARIUS · Step 7: Harvest, dry, cure

Drying: Hang whole branches (or whole plant, trimmed or not) in a dark room at 18–20°C and 55–60% RH for 10–14 days. The "snap test" on a small stem — it bends, bends, then snaps cleanly — means it's ready to jar. Too fast (under a week) locks in chlorophyll. Too slow risks mould.

Curing: Jar the dried buds loosely in glass mason jars at 55–62% RH. Burp the jars (open for a few minutes) daily for the first week, every few days for the second, weekly after that. Two-way humidity packs (Boveda 62%) make this nearly foolproof. A proper cure takes 4–6 weeks minimum; the terpene profile keeps improving for months.

Common mistakes and how to avoid them

• Overwatering seedlings and young plants. Wet medium starves roots of oxygen. Lift the pot — if it's heavy, wait.
• pH drift. Check runoff pH weekly in soil/coco. Nutrient lockout from pH drift mimics deficiencies and sends growers chasing the wrong problem.
• Ignoring VPD. 80°F and 30% humidity is brutal on plants, even if both numbers look "fine" individually. Check VPD, not just temperature and RH separately.
• Harvesting too early. The last 10–14 days add weight and potency. Patience beats enthusiasm.
• Skipping the cure. A two-week cure is noticeably worse than a four-week cure. Don't put in 14 weeks of work and smoke it harsh.

Yield expectations (honestly)

Any "500g per plant" claim without context is marketing. Under a 250W LED in an 80×80 tent, with feminised photoperiod genetics, competent training, and a clean run, a dried-and-cured yield of 200–400g total for 2–4 plants is a realistic target for experienced home growers. First grows often come in at half that. Autoflowers in the same space typically produce 100–250g total. Outdoor yields in Northern Europe vary enormously with latitude, weather, and how much the birds and the neighbours notice.

AZARIUS · Common mistakes and how to avoid them

AZARIUS · Yield expectations (honestly)

Azarius cannabis seeds and grow supplies

Azarius has sold cannabis seeds since 1999 and carries breeder-direct genetics from Dutch Passion, Paradise Seeds, Royal Queen Seeds, Ministry of Cannabis, Sensi Seeds, and Barney's Farm, alongside tents, LED lights, nutrients, and IPM supplies. If you want a starting point: a feminised photoperiod variety with a documented short flowering time, an 80×80 tent kit with a carbon filter, and a basic bottled nutrient line for your chosen medium. That's the setup we'd run ourselves for a first grow.

AZARIUS · Azarius cannabis seeds and grow supplies

Last updated: April 2026