How to Grow Indoor Plants – Your Complete Guide
Thinking about growing plants indoors and starting your first indoor grow? Exciting times!
Growing indoors gives you full control over your plants, their climate and their potential – and once you get going, it’s a hobby that’s as rewarding as it is addictive.
If you’re new, don’t worry. We’ve put together everything you need to know, step by step, to get set up, grow healthy plants and deal with challenges along the way.
Whether you want to start simple with a small tent or build a fully kitted-out grow room, you’ll find clear advice here that works in the real world.
To help you even more, check out our Full Grow Kits – hand-picked setups that take the guesswork out of choosing the right gear. They’re designed by growers, for growers, so you can get started with confidence.
We’re here to help at every stage.
You’ll find GroWell shops across the UK where you can see the products in action, ask questions face to face, and get straight-up, unbiased advice from staff who’ve been growing for decades. Pop in, say hello, and tap into that experience whenever you need it.
Indoor growing doesn’t have to be complicated – and with the right guidance, it’s something anyone can enjoy. Let’s get started.
Getting Set Up for Growing Indoors
Getting set up is about creating the perfect environment from the start – planning your space, lighting, and extraction so everything runs smoothly before a single seed or cutting goes in.
Step 1: Grow Room Planning: What to Sort Before You Set Up
Choose your space, power, water, flooring and waste management. The right plan makes everything easier later.
Step 2: Setting Up a Grow Tent
Start by measuring the space you're eyeing up and choose the right size. Grow tents come in several variations to suit most spaces, including pitched versions ideal for making use of a loft space.
Step 2: Installing an Extraction System
How to size extract/intake fans, choose filters, and assemble ducting for clean, odour‑free, temperature‑stable grows.
Step 3: Lighting Configuration: Ballasts, Reflectors, LEDs & Timers
Understand ballasts and reflectors, dial in timers, and get the most from modern full‑spectrum LEDs.
Step 4: Lighting Configuration for Indoor Growing: Hanging Heights
Recommended hanging heights for common fixtures so you deliver the right PPFD without stressing plants.
Hydroponic Systems (Choose Your Method)
Growing in Hydroponic Systems: An Overview
NFT, Flood & Drain, Drip, DWC, Pot‑ponics and fabric pots compared so you pick the best fit for your space and goals.
Growing with DWC: A Deep Water Culture Guide
Mineral feeds only, water‑level management, temperature control and root‑zone hygiene for monster plants.
Growing in Coco: A Complete Guide
Charging coco, Cal‑Mag management, run‑off targets and pairing with RhizoPots for dense root mass.
How to Grow Plants Indoors - Start to Finish Steps
Starting Your Plants off
First things first, are you starting off from a seed, or a cutting?
Seeds offer fresh genetics, strong taproots and a lower risk of hidden pests, but they take longer and can vary; cuttings root faster and guarantee identical traits to the mother plant, but may inherit pests or weaknesses and rely on having a healthy donor.
Starting Off Seeds – A Step‑by‑Step Guide
Prepare cubes, set pH/CF, sow, and manage humidity so seeds pop fast and evenly.
Taking Cuttings – A Step‑by‑Step Cloning Guide
From choosing mother stock to cutting technique, rooting gels and propagator settings.
Ramp Up Rooting with Your Propagator
Aeroponic vs. Hi‑Top tests, plus transplant steps for coco, soil and hydro so new roots never stall.
Root Boosters: Do They Work?
Side‑by‑side results and when to use boosters for denser, faster‑forming root systems.
Transplanting & Moving Up
Transplanting is all about giving your young plants more space to thrive – move them carefully into bigger pots or a main system at the right time and you’ll keep growth smooth instead of setting them back.
Transplanting Your Cuttings and Seedlings
Exactly how to pre‑soak media, set strengths and place seedlings without shocking roots.
Moving Into a Main System
Step‑by‑step moves into bubblers, NFT or larger pots, with temperature and stability checks.
Growing Plants (The Vegetative & Flowering Cycle)
The vegetative and flowering cycles are where your plants really take shape – build strong leafy growth under long light hours, then switch to 12 hours on, 12 hours off to trigger blooms and maximise yields.
Vegetative Growth
Light cycles, training, support, feeds and environment to build a strong, leafy structure before bloom.
Flowering (LED & HPS Lighting, Feeds & Harvesting)
Switching to 12/12, bloom nutrition, humidity targets, and harvesting strategies.
Nutrition, Water & Environment
Getting nutrition and water right means balancing pH, CF/EC and oxygen levels so plants can absorb exactly what they need, when they need it, without stress or lockout.
Mixing Nutrient Solutions
Hard vs. soft water, pH and CF targets, element availability by pH, meter quick guides and a full mixing method.
Managing Your Oxygen Levels in Hydroponic Systems
Pump and air‑stone matching, pre‑soaking stones, bubble spread and why oxygen acts like a hidden nutrient.
Managing Your Grow Room & Nutrient Temperatures
Target room temps vs. nutrient temps, when to use heaters/chillers, and practical climate tips for stable growth.
Protection, Pests & Problem‑Solving
Protection, pests & problem-solving is all about spotting issues early, keeping your grow room clean, and knowing how to tackle bugs or plant stress before they affect your harvest.
Plant Pest Control
Identify leaf miners, sciarid fly (fungus gnats), spider mites and thrips. Treatments, predators and prevention routines.
Troubleshooting Guide for Growing
Fast diagnosis by symptom: lights, propagation, leaves, growth and roots — with first actions and further fixes.
