Grow more than you think
in the space you have

A 2m² balcony can produce fresh salads throughout summer, herbs year-round, and meaningful quantities of tomatoes, peppers, and courgettes. What it requires is not space but the right approach to containers, soil, and crop selection.

Understanding Your Balcony's Conditions

Before selecting crops, two variables determine what will grow well: light and exposure. Most fruiting vegetables (tomatoes, peppers, courgettes, cucumbers) require a minimum of 6 hours of direct sunlight per day. A south or west-facing balcony with unobstructed sun from late morning onward is ideal. A north-facing balcony or one heavily shaded by a building above will not support fruiting crops but is perfectly suited to salad leaves, spinach, kale, herbs, and some climbing beans.

Exposure to wind is the second variable. Balconies above the third floor in exposed positions can experience wind that desiccates plants rapidly and damages fragile stems. Wind breaks (trellises with climbing plants, solid balustrades, strategic placement) significantly improve growing conditions on exposed balconies. Watering frequency doubles on windy balconies compared to sheltered ground-level positions.

Containers: The Variables That Determine Success

Container selection is the most consequential decision in balcony growing. The two rules that override everything else: containers must be large enough for the crop's root system, and they must have adequate drainage.

• Tomatoes: minimum 30–40 litres per plant. Smaller containers produce smaller, more drought-stressed plants that are more susceptible to blossom end rot and inconsistent fruiting. Cherry tomatoes tolerate smaller containers (20L) better than beef or plum varieties.
• Peppers: minimum 15–20 litres per plant.
• Courgettes: minimum 40–50 litres — they are greedy feeders and large plants. One well-sited courgette in a large container produces more than most families can eat.
• Salad leaves: 5–15 litres per window box section. These are the most forgiving and productive crops for limited space, producing continuous harvests with cut-and-come-again varieties.
• Herbs: individual 1–3 litre pots, or a combined herb trough of 10–15 litres for a mixed selection.

Terracotta is attractive but dries out rapidly — add a saucer underneath during summer and check moisture daily. Plastic or fabric pots retain moisture better and are significantly lighter, which matters for balcony load limits (check your building's load specifications before placing heavy containers; saturated soil is surprisingly heavy).

Soil: Never Use Garden Soil in Containers

Garden soil in containers compacts rapidly, preventing drainage and oxygen from reaching roots — the leading cause of container plant failure. Use a quality peat-free potting mix for most crops, and add approximately 20% perlite or horticultural grit to improve drainage and aeration. For fruiting crops (tomatoes, peppers, courgettes), add a slow-release granular fertiliser at planting and supplement with a weekly liquid tomato feed from first flower set onward.

Crops by Space and Difficulty

Crop	Min. Container	Light Needed	Difficulty	Expected Yield
Cherry tomatoes	20L	6+ hr sun	Medium	2–4 kg/plant/season
Salad leaves (cut-and-come)	5L/section	3+ hr sun	Easy	Continuous harvest, Mar–Oct
Basil	1–3L	5+ hr sun	Easy	Continuous with regular trimming
Chillies	10–15L	6+ hr sun	Easy	30–100+ fruits/plant
Courgette	40–50L	6+ hr sun	Easy (if container large enough)	1 per day at peak
Spinach / chard	5L	2–4 hr sun	Easy	Continuous, tolerates shade
Climbing beans	20L	5+ hr sun	Medium	250–500g/plant/season
Strawberries	5L/plant	5+ hr sun	Easy	250–500g/plant/season

Most indoor plant deaths are caused by one of three things: overwatering, wrong light, or wrong plant for the environment. Understanding these three variables turns chronic plant-killers into people who maintain thriving plants for years.

Why Most Indoor Plants Die

The most common cause of indoor plant death is overwatering — a counterintuitive failure mode because it is driven by care and attention rather than neglect. Plant owners who check their plants frequently and water regularly are often the ones most likely to overwater, because the visual appearance of dry compost triggers the watering impulse even when the roots are still adequately moist or, worse, already sitting in anaerobic, waterlogged soil.

Root rot — caused by roots sitting in wet soil with no oxygen — presents no visible symptoms until significant damage is done. By the time leaves yellow and wilt, the root system is often already severely compromised. The correct watering approach for almost all popular indoor plants is to water thoroughly and then wait for the compost to partially or fully dry before watering again. The interval depends on the plant, the pot size, the light level, and the season — not a calendar schedule.

The Light Variable: More Important Than Any Other

Indoor light levels are dramatically lower than they appear. What feels like a "bright room" to human eyes is often 10–50 times dimmer than outdoor conditions on a cloudy day, because human eyes adapt automatically to light levels across a range that plant photosynthesis does not. A plant placed in what appears to be a well-lit corner may be receiving only a fraction of the light it requires.

The practical rule: place light-demanding plants (most fruiting plants, many herbs, succulents and cacti) within 1–2 metres of a south or west-facing window. Medium-light plants (most popular tropicals — pothos, philodendrons, monsteras, peace lilies) can tolerate positions up to 3–4 metres from a window. Low-light plants (snake plants, ZZ plants, cast iron plants, some ferns) tolerate positions further from windows but none genuinely thrive in deep shade — they survive it.

The 10 Indoor Plants That Are Genuinely Hard to Kill

Plant	Light	Water	Why It Survives Neglect
Sansevieria (snake plant)	Low–high	Every 2–4 weeks	Stores water in leaves; tolerates drought and low light
Zamioculcas (ZZ plant)	Low–medium	Every 2–4 weeks	Stores water in underground rhizomes; almost impossible to overwater
Pothos / Epipremnum	Low–high	When soil is dry	Trails or climbs; extremely adaptable; wilts visibly before damage occurs
Monstera deliciosa	Medium–bright indirect	Weekly in growing season	Tolerates irregular watering; grows dramatically in good light
Spider plant	Low–high	When soil is dry	Stores water in tubers; one of the most adaptable houseplants
Aloe vera	Bright	Every 3–4 weeks	Succulent; stores water in leaves; only killed by overwatering
Peace lily	Low–medium	When leaves begin to droop slightly	Communicates watering needs visibly; recovers well from wilt
Rubber plant (Ficus elastica)	Medium–bright indirect	Every 7–14 days	Tolerates lower light than expected; few pests; striking appearance

Fresh herbs are the highest-value-per-square-centimetre use of any indoor growing space. A windowsill with six herb pots produces flavour that no supermarket herb pack can match and reduces both herb waste and grocery spending significantly.

Why Supermarket Herbs Fail

The potted herbs sold in supermarkets are not designed to thrive long-term — they are grown at high density under controlled conditions for short-term visual appeal and rapid sale. Each small pot typically contains 15–30 seedlings packed tightly together, producing lush growth that cannot be sustained in a home environment without immediate intervention. Left in the original supermarket pot, most herbs deteriorate within 1–3 weeks because the overcrowded roots exhaust the limited compost and compete for space.

The intervention that turns a supermarket herb into a long-lived plant: immediately separate the seedlings (or at minimum divide the root ball into 2–3 sections) and repot into individual 10–15cm pots with fresh, well-draining compost. Placed in a south-facing window with adequate light, the repotted herbs will stabilise and produce continuous harvests for months or years.

The Essential 6 for a Kitchen Herb Garden

• Basil: the most demanding of the six — requires warm temperatures (above 15°C at all times) and 5–6 hours of direct sun. Pinch out flower buds as they appear; once basil flowers and sets seed, the flavour deteriorates and the plant declines rapidly. Harvest from the top down, removing whole stems rather than individual leaves. Never refrigerate cut basil.
• Rosemary: Mediterranean native that is extremely drought-tolerant but intolerant of waterlogged soil. Needs a gritty, free-draining compost mix and the brightest window available. Slow-growing but essentially indestructible once established. Add 30% horticultural grit to the compost at planting.
• Thyme: same requirements as rosemary — bright light, excellent drainage. One of the few herbs that genuinely improves with neglect; slightly drought-stressed thyme has more concentrated essential oils and stronger flavour than well-watered thyme.
• Chives: the most shade-tolerant of the six, and the one that recovers best from hard harvesting. Cut to 2–3cm above the compost when harvesting and they regrow within 2–3 weeks. Chive flowers are edible and attractive; leave some stems to flower for a visual bonus.
• Mint: grows aggressively and must be kept in its own pot — never planted with other herbs, as it will rapidly outcompete and displace them. Tolerates shadier positions than other herbs. Harvest regularly to prevent it from flowering and to maintain compact, leafy growth. Very cold-hardy; can be left outdoors in sheltered positions year-round.
• Parsley: the slowest to establish of the six but one of the most productive once going. Requires consistent moisture (unlike thyme and rosemary) and 4–5 hours of sun. Flat-leaf parsley is more flavourful than curly; use curly as a garnish only. Parsley is biennial — it produces well for one year, flowers in the second, then dies. Replace annually for continuous production.

Harvesting: The Habit That Keeps Plants Productive

Regular harvesting is not optional for productive herb growing — it is the management technique that keeps plants in their productive vegetative state. Herbs that are not regularly harvested redirect energy to flowering and seed production, at which point the flavour of the leaves deteriorates and the plant's productive life effectively ends. Regular harvesting delays this process significantly.

The rule for all herbs: never take more than one-third of the plant at any one harvest, and harvest from the top rather than the bottom (which stimulates bushier, more compact growth). For basil, pinch out any flowering stems immediately upon appearance — the plant will produce new growth for weeks longer without this intervention.