Growers' Guides
Plant Pot Sizes: Litres to cm, How to Measure, Which Size to Use
Plant pot sizes in litres and the centimetres our pot pages give, how to measure a pot, which size for seedlings and tomatoes, and when to pot on.
Grow Room Setup: Sheeting, Flooring, Ducting and Loft Grow Tents
How to set up a grow room in a spare room, cupboard or loft: light-proof sheeting, a waterproof floor, ducting out through a wall and ceiling hangers.
Dutchpro Feed Chart: Soil and Hydro/Coco A & B Week by Week
The Dutchpro feed chart for Original Soil and Hydro/Coco A & B, week by week in ml per litre, with Take Root, Multi Total, Silica and Explode.
How to Calibrate a pH Pen or Meter, Check EC and Store the Probe
How to calibrate a pH pen in pH 7 and pH 4 buffer step by step, how often to do it, how to check an EC meter, and how to store and clean the probe.
Mycorrhizae, Trichoderma and Beneficial Bacteria for Plants
Mycorrhizae, Trichoderma and beneficial bacteria: what they do, when to add them in soil, coco or hydro, and the microbial products we sell compared.
Grow Lights for Indoor Plants and Seedlings: Which and How Close
Grow lights for indoor plants and seedlings: do they work, why seedlings go leggy, which light suits a windowsill or greenhouse, and how close to hang it.
How to Grow Chillies Indoors: Seed to Harvest and Overwintering
How to grow chillies indoors from seed: when to sow, heated propagators, grow lights, pots and feeds, a small tent, and how to overwinter a chilli plant.
How to Dry Chillies and Herbs: Drying Nets, Airflow and Storage
How to dry chillies and herbs indoors on a drying net: when to pick, the dark and airy conditions to aim for, how long it takes and how to store them.
How to Grow Microgreens, Herbs and Salad Indoors in Winter
How to grow microgreens, herbs and salad leaves indoors through winter: which grow light and hours, trays, the Tray2Grow, NFT set-up, pots and feeds.
Seaweed Extract, Humic and Fulvic Acid, Amino Acids for Plants
What seaweed extract, humic and fulvic acid, amino acids and vitamin tonics do for plants, which can be sprayed, and the ones we sell compared by dose.
Grow Tent Ventilation: Passive Intake or an Intake Fan?
Grow tent ventilation explained: passive vents or an intake fan, negative pressure, bug screens, shutters, ducting and how to run two fans together.
House & Garden Feed Chart: Aqua Flakes and Cocos Week by Week
The House & Garden feed chart for Aqua Flakes and Cocos week by week, per US gallon and in ml per litre, with Roots Excelurator and Top Shooter.
Which Potting Soil? Biobizz, Canna Terra, Plagron and Gold Label
Biobizz All Mix vs Light Mix, Canna Terra Professional vs Plus, Plagron Batmix and Gold Label compared: how much food each soil carries and when to feed.
Soil Amendments and Living Soil: Worm Castings, Frass, Pre-Mix
Soil amendments for living soil: what worm castings, insect frass, Biobizz Pre-Mix and mycorrhizae do, which soils already have them and when to add each.
Dripper Systems: Origin, IWS Dripper Pro and DIY Drip Lines
How a hydroponic drip irrigation system works, the Origin and IWS dripper systems we sell, the parts to build your own, and how to keep drippers clear.
Greenhouse, Grow Tent and Grow Room Heaters: Which to Choose
Greenhouse and grow tent heaters compared: tube heaters, fan heaters and the Thermoforge T7, the temperatures to aim for and how to add a thermostat.
Aphids (Greenfly, Blackfly) and Whitefly: How to Get Rid of Them
How to spot aphids (greenfly and blackfly) and whitefly on chillies, tomatoes and indoor plants, and how to get rid of them by hand, spray or dust.
PK Boosters and Bloom Boosters: PK 13/14 Doses and When to Add
What a PK booster does, what PK 13/14 and 9/18 mean, when to add Canna PK 13/14 or Canna Boost, and the boosters and stimulants we sell compared.
Sowing Seeds Indoors: How to Germinate, Prick Out and Harden Off
How to germinate seeds indoors, choose a seed propagator, prick out and transplant seedlings, what to feed them and how to harden them off.
Which Nutrients for Soil, Coco or Hydro? Base Feeds Compared
Which plant nutrients to buy for soil, coco or hydroponics: the base feeds we sell compared, Plant Magic or Biobizz, hard or soft water, and how to choose.
Why Are My Plant Leaves Turning Yellow? Causes and Fixes
Why plant leaves turn yellow or burn, from tomatoes to houseplants: watering, feed, pH, light, heat, pests or a deficiency, and what to check first.
Hesi Feed Chart: Soil and Coco Grow Schedules Week by Week
The Hesi feed chart for soil and coco, week by week in ml per 10 litres: TNT Complex, Bloom Complex, Hesi Coco, PK and boosters, from Hesi's own schedules.
Grow Tent Setup: How to Set Up a Grow Tent, Step by Step
How to set up a grow tent step by step: the spot, the tent, light, extraction, intake, timers and a test run. Plus what our grow tent kits include.
Grow Tent Humidity: How to Lower or Raise It
Grow tent humidity targets for each stage, why it climbs at lights-off, how to lower or raise it, and when you need a humidifier or a dehumidifier.
Root Rot (Pythium): How to Spot, Fix and Prevent It
What root rot (pythium) looks like, what causes brown, slimy roots in hydroponics, soil and coco, how to prevent it and how to fix it.
Root Stimulants, Rooting Gels and Rooting Hormone: Which to Use
Rooting gel or root stimulant? What Clonex rooting hormone does, when to use a root stimulant, and how the ones we sell compare by dose and timing.
Grow Room Running Costs: How Much Electricity a Grow Light Uses
How much electricity a grow light uses and what a grow tent costs to run: kWh a day for lights from 150 W to 1030 W, LED vs HPS, and ways to cut the bill.
Hydroponics and Growing Terms Explained: A Growers' Glossary
Hydroponics and growing terms explained in plain English, from EC, pH and PPFD to VPD, NFT and run-to-waste, with links to our full guides.
Flood and Drain Systems: How Ebb and Flow Hydroponics Works
How flood and drain (ebb and flow) hydroponics works, the IWS systems we sell, what to grow in, tank care, and flood and drain vs DWC, NFT and Autopot.
Cal-Mag Guide: Calcium and Magnesium Deficiency in Plants
What cal-mag is, who needs it, how to tell calcium, magnesium, nitrogen and iron deficiency apart, and how the cal-mag products we sell compare.
Perlite vs Vermiculite: What They Are and When to Use Each
What perlite and vermiculite are, how they differ, which to use for seeds, cuttings, soil and coco, and the soils and mixes we sell with perlite in them.
Clay Pebbles and Rockwool Cubes: How to Use Them in Hydroponics
What clay pebbles and rockwool are, how to rinse, soak and plant in them, which hydroponic systems each suits, and how they compare with coco.
Reverse Osmosis (RO) Water for Growing: Do You Need a Filter?
What reverse osmosis (RO) water is, why growers use it on hard tap water, the RO filters we sell, what to add back, and when you can do without one.
Powdery Mildew: What Causes It and How to Get Rid of It
Powdery mildew in a grow room or greenhouse: what causes it, how to tell it from grey mould (botrytis), and how to get rid of it with drier, moving air.
Coco Coir Guide: Choosing, Feeding and Reusing Coco
What coco coir is, the coco mixes worth buying, how it compares with clay pebbles and rockwool, and how to feed and reuse it.
Fabric, Air-Pot or Plastic Pots? How to Choose (and What Size)
Air-Pots, fabric plant pots and plastic pots compared: how air-pruning works, the best fabric pots for hand or self-watering, and which size to buy.
VPD Chart: What Vapour Pressure Deficit Means for Your Plants
VPD explained in plain terms, with a chart by temperature and humidity, the ranges to aim for at each stage, and how to measure and control it.
pH and EC: Meters, Test Kits and pH Up/Down
How to test pH with a meter or a pH test kit, measure EC, read the makers' targets, use pH Up and pH Down, and calibrate and care for a meter.
Propagators and Cuttings: How to Root Cuttings
How to take cuttings that root: choosing a propagator, the starter plugs, Clonex rooting gel, which propagation light and tent, and when to open the vents.
Autopot Systems Explained: How They Work and Which to Buy
How Autopot works without pumps or power, which system and pot size suits your space, what to grow in, and how to set it up.
How to Size an Extraction Fan and Carbon Filter for a Grow Tent
Work out the inline fan and carbon filter your grow tent needs: tent volume, air changes a minute, the filter allowance, and a table by tent size.
What Size Grow Tent Do I Need?
Plants per tent by pot size, the height a light needs, where Budbox, Secret Jardin and AC Infinity tents fit, loft tents, and kit or separate parts.
LED Grow Light Wattage by Tent Size (and LED vs HPS)
How many watts of LED a tent needs: 300-500 W/m² in flower, a table by tent size, the Maxibright, Gorilla and LUMii fixtures that fit, and LED vs HPS.
LED or HPS? Why the Best Growers Use Both
Tom's view from twenty years in the shop: run LED as the main light and add a dimmable HPS, metal halide or CMH for flowering weeks 3-7 for a better finish.
Fungus Gnats (Sciarid Flies): How to Get Rid of Them
Small black flies around your pots? They're fungus gnats, or sciarid flies. How to spot them, why they appear and how to get rid of them for good.
Thrips on Plants: How to Spot the Damage and Get Rid of Them
Silvery streaks and black dots on your leaves? How to spot thrips and their damage, why they're hard to shift, and how to get rid of them.
Red Spider Mite: How to Spot It and Get Rid of Spider Mites
What spider mites and their eggs look like, the speckled leaves and webbing they leave, why they spread so fast and how to get rid of red spider mite.
Advanced Nutrients Feed Chart: Sensi Grow & Bloom by Week
The Advanced Nutrients feed chart for pH Perfect Sensi Grow and Bloom (and Sensi Coco): base and additive doses week by week in ml per litre.
Athena Feed Chart: Blended and Pro Line Schedules (Metric)
The Athena feed chart in metric: Blended Line and Pro Line doses week by week, with EC, pH, pre-soak and flush from Athena's own schedules.
Plant Magic Feed Chart: Coco, Hydro and Soil Schedules
The Plant Magic feed chart for coco, hydro and soil: Essential and Ultimate schedules week by week in ml per litre, from Plant Magic's own charts.
Canna Coco Feed Chart & Grow Guide: A & B, Additives, EC by Week
The CANNA COCO feed chart and Canna grow guide: a week-by-week grow chart for A & B, Rhizotonic, CANNAZYM, CANNABOOST and PK 13/14, and the EC to aim for.
Canna Terra Feed Chart: Vega, Flores and Additives by Week
The CANNA Terra feed chart and grow guide for soil: Terra Vega and Flores doses week by week, the additives, and the EC to aim for, from CANNA's schedule.
Canna Aqua Feed Chart for Hydroponics: Doses and EC by Week
The CANNA Aqua feed chart and grow guide for recirculating hydroponics: Aqua Vega and Flores A & B doses by week, the additives and the EC to aim for.
Biobizz Feed Chart 2026: All·Mix and Light·Mix Schedules
The Biobizz feed chart week by week for Light·Mix, Coco·Mix and All·Mix: Bio·Grow, Bio·Bloom, Top·Max, Root·Juice and the boosters in ml per litre.
The Importance of Airflow, Temperature & Humidity in a Grow Room
Creating the perfect environment inside your grow room isn’t just a matter of comfort for your plants - it’s the foundation of healthy growth, efficient…
What You Need to Grow Indoors: The Kit Checklist
What you need to grow indoors as a beginner: tent, LED, fan and filter, hangers, timer, hygrometer, pots, soil or coco, feed, pH kit and our kits.