Crop Application · Herbs & Leafy Greens
Short cycles, high turnover — substrate that starts at zero.
Herbs and leafy greens have the narrowest EC tolerance of any commercial crop. Ultra-low native EC gives you total control from day one, without conditioning or adjustment.
< 0.3
Native EC
60–70%
WHC required
4–8 wks
Crop cycle
The Challenge
What growers lose when the substrate EC isn't at zero from the start.
>0.5
Native EC forces adjustment
Most substrates carry native EC above 0.5 mS/cm. Basil EC-stresses at anything above 1.2 mS/cm in-slab. That gap forces a conditioning flush before you sow — adding time and complication to every cycle.
30%
Low WHC means more labour
Peat at 30% WHC requires more frequent irrigation to prevent wilting in fast-cycle crops. Managing 8–10 trays simultaneously in a propagation tunnel means any irrigation gap shows up immediately in tip burn.
1 cycle
Single-use economics
Most peat propagation mixes are designed for one use. At 4–8 week cycles with multiple crops per year, replacing substrate every cycle adds material cost to an already margin-tight category.
The Coir Fix
What zero-EC, high-WHC coir changes for herb production.
< 0.3
Sow immediately — no conditioning
Native EC below 0.3 mS/cm straight from hydration. Activate and sow directly. No flush, no conditioning run-through. First nutrition is 100% under your control from day one of every cycle.
60–70%
WHC that holds through the cycle
60–70% WHC means substrate stays in the optimal moisture range through a full overnight without irrigation. One fewer decision per tunnel — and basil and lettuce stay in the safe zone without constant monitoring.
3 cycles
2–3 crop cycles per substrate charge
Flush with EC 0.5 water between cycles. Coir reuses for 2–3 full cycles before replacement. The per-cycle substrate cost drops significantly compared to single-use peat.
Crop Type Guide
Key numbers per herb type.
Basil & Soft Herbs
EC Target
1.5 – 2.0 mS/cm in-slab
Drain %
15 – 20%
Low drain, frequent short shots. High WHC critical — basil shows tip burn rapidly under any water stress. Keep WHC above 60% at all times.
Lettuce & Leafy
EC Target
1.2 – 2.0 mS/cm in-slab
Drain %
15 – 25%
Fine pith for moisture retention. Multiple cut-and-come-again harvests possible. Flush between cuts with EC 0.5 water.
Chives & Robust Herbs
EC Target
2.0 – 2.5 mS/cm in-slab
Drain %
20 – 25%
Slightly higher EC tolerated. Suits 70:30 coir/perlite blend for improved drainage in humid tunnels.
Irrigation Protocol
Short shots. High frequency. Clean cycles.
High-frequency short irrigation shots maintain the WHC window herbs need. The balance between frequency and shot size determines tip burn risk more than any other variable.
01
Substrate prep
Use briquettes or fine-grade coir pith. EC < 0.3 native — no feed for the first 5–7 days. Activate with clean water (EC ≤ 0.5) and sow immediately. Do not buffer before sowing.
02
Irrigation regime
80–120 ml shots every 45–60 min during daylight. Maintain WHC above 60%. Allow mild overnight drying — not below 45%. Do not let substrate fully dry between shots.
03
Harvest cycle
Cut-and-come-again harvests are possible for leafy crops. Between cycles, flush substrate with EC 0.5 water. Test post-flush EC before reuse. Replace after 2–3 cycles or if EC > 2.5 post-flush.
Agronomic Support
Substrate specification for your operation.
Share your crop, target EC, system format, and season length — we'll specify the right substrate and provide technical support for your first grow.
Talk to our agronomy team
Substrate guidance matched to your crop, system format, and target EC window.
Recommended Substrates
Ready to trial coir?
Substrate guidance for your herb or leafy green operation.
Share your crop, cycle length, and irrigation setup — we'll specify the right substrate grade and confirm the EC protocol for your first cycle.