Grow bag sizes for every vegetable, with litres, the right soil mix, where to place them on a terrace or balcony, watering, and how long grow bags last in India.
Updated 30 September 2026
Part 1
Why grow bags suit Indian terraces
Grow bags are light, cheap, easy to move and drain well, so they suit terraces where weight and waterproofing matter. Good ones are made of UV-stabilised HDPE or fabric that lasts two to three seasons in Indian sun. Because they can be picked up, you can clean and check the floor under them, which you cannot do with a built bed.
Part 2
Grow bag size for each vegetable
Match the bag to the root depth of the crop. A bag that is too small dries out quickly in summer and limits the harvest; one that is far too big wastes soil and adds weight. Sizes in India are usually given as diameter × height in inches.
| Bag size (inches) | Holds about | Grow | Plants per bag |
|---|---|---|---|
| 9 × 9 | 9 litres | Coriander, spinach, methi, mint, herbs, spring onion | A small patch of greens, or 1 herb |
| 12 × 12 | 22 litres | Tomato, chilli, brinjal, capsicum, okra | 1 |
| 15 × 15 | 43 litres | Gourds, beans on a trellis, cucumber, small fruit plants | 1–2 |
| 18 × 12 | 50 litres | Leafy greens in rows, radish, carrot, several herbs together | Several |
| 24 × 12 | 89 litres | A mixed bed of greens, or a small fruit tree | Several, or 1 tree |
Part 3
The soil mix
Do not fill bags with garden soil alone; it packs down and drains poorly. A reliable mix is roughly equal parts cocopeat, compost or vermicompost, and red soil or garden soil, with a handful of neem cake. Leave an inch at the top for watering and mulch.
Top up with compost at the start of each season and loosen the surface. Replace the mix every two or three seasons, or sooner if a crop had disease.
- 1 part cocopeat, soaked and squeezed: keeps the mix light and holds water
- 1 part compost or vermicompost: feeds the crop
- 1 part red soil or garden soil: gives body and holds nutrients
- A handful of neem cake per bag: helps keep soil pests down
Part 4
Placement and watering
Most vegetables need at least five to six hours of direct sun. Keep bags on bricks or a stand so water drains and air reaches the base, and so the terrace floor under them can dry. Group bags along the parapet walls and keep the drain outlets clear.
In summer, bags can need water every day; a drip line with a timer on each bag makes this reliable and keeps the floor from being flooded with a hose.
Part 5
Are grow bags safe for the terrace?
Yes, when they are raised off the floor and the drains are kept clear. They are the lightest way to grow vegetables on a roof. Problems come from bags left standing in water on the slab or soil spilling into the drains, not from the bags themselves.
Questions
Which grow bag size is best for tomatoes?
A 12 × 12 inch bag, holding about 22 litres of mix, suits one tomato plant. Give it a stake or cage and at least six hours of sun.
What size grow bag for chilli and brinjal?
12 × 12 inches, one plant per bag. Smaller bags dry out too quickly in summer and give fewer fruits.
What is the best soil mix for grow bags?
Equal parts cocopeat, compost or vermicompost, and red soil or garden soil, with a handful of neem cake. Never use garden soil alone; it packs down and drains poorly.
How long do grow bags last?
Good UV-stabilised HDPE or fabric grow bags last two to three seasons in Indian sun. Top up the soil with compost each season and replace the mix every two or three seasons.
Do grow bags damage the terrace?
Not when they stand on bricks or a stand so the floor under them dries, and the drains are kept clear. They are the lightest and safest way to grow vegetables on a roof.
How often should I water grow bags?
In summer, often every day; in winter and the monsoon, much less. Check by pushing a finger into the mix, or fit a drip line with a timer on each bag.