Grow media for indoor growing: potting soil, coco coir, perlite, clay pebbles and rockwool from Plagron, BioBizz, Canna, Grodan and Eazy Plug, in 50 L bags or on pallets. In short: soil is more forgiving and works at pH 6.0–7.0; coco and rockwool grow faster, but need nutrients at almost every watering and pH 5.5–6.5.
The growing medium decides how often you water, how much feed you give and how much room you have for mistakes. The table sums up the main differences.
| Growing medium | pH | Nutrients | Watering | Best for |
|---|---|---|---|---|
| Lightly fertilised soil (light mix) | 6.0–7.0 | Small reserve: start feeding early | When the top 2–3 cm are dry | Seedlings, cuttings, growers who want control |
| Pre-fertilised soil (all mix) | 6.0–7.0 | Reserve for the first weeks | When the top 2–3 cm are dry | Less feeding at the start |
| Coco coir | 5.5–6.5 | Almost none: coco nutrients at every watering | Often, never let it dry out | Fast growth, automatic watering |
| Rockwool | 5.5–6.5 | None (inert) | Frequent or automatic | Cuttings, hydroponics |
| Clay pebbles | 5.5–6.5 | None (inert) | DWC, flood and drain | Hydroponics, drainage layer |
Soils for indoor growing differ mainly in their starting charge of nutrients. A light mix contains little feed: it suits seedlings and cuttings and lets you decide when and how much to feed, but you need to start feeding early. A pre-fertilised all mix holds a bigger reserve, so you feed little or nothing in the first weeks; for freshly sprouted seedlings and newly rooted cuttings it can be too rich.
Whichever soil you choose, follow the manufacturer's feed chart for that medium.
Allow for the pot volume plus 5–10%, because soil settles after the first watering. A 50 L bag fills about 4 pots of 11 L, 3 pots of 14 L or 2 pots of 18 L. For large tents or several cycles a pallet is better value. SK square pots from 3.5 to 25 L are in the pots category.
At Gro.w.LaB all prices are in Swiss francs, including Swiss VAT. We deliver throughout Switzerland by Swiss Post; pallets travel by courier. For technical advice, send an email to our support team or call +41 79 359 67 58; you can also visit the shop in Quartino by appointment.
For beginners soil is more forgiving: it buffers pH and nutrients and is watered every 2–3 days. Coco grows faster but needs frequent watering with nutrients at pH 5.5–6.5.
It makes soil lighter and airier and drains excess water, so the roots do not run short of air. Growers usually add 10–30% by volume.
About 11–12 L, because soil settles after the first watering. A 50 L bag is enough for 4 pots of 11 L.
Light mix if you start from seedlings or cuttings or want to control feeding yourself; all mix if you want to feed less in the first weeks. Either way, keep the water at pH 6.0–7.0.
