DOC №210SEC: GUIDESREV: 2026-06-02AI ASSISTED
Hydroponic Parameter Reference — pH, EC, DLI & Harvest Time for 55 Crops
Target pH, EC, DLI and days-to-harvest for 55 hydroponic crops in one chart — leafy greens, herbs, fruiting crops, and microgreens. Sourced and fully metric.
BY ROOTLESS FARM
Quick answer
This page consolidates the core growing parameters — target pH, EC, DLI, and days to harvest — for every one of the 55 crops in the Rootless Farm plant database, in one reference. Use it to plan a reservoir that mixes well across crops, to pick compatible plants for a shared system, or to sanity-check a target before mixing nutrients. Each crop name links to its full guide.
All values are metric (EC in mS/cm, DLI in mol/m²/day) and represent conservative working ranges for home and small commercial setups. They are the same ranges published on each crop's individual guide.
How to read this chart
- pH — the nutrient-solution acidity target. Most hydroponic crops sit between 5.5 and 6.5; brassicas and a few others tolerate up to 7.0–7.5.
- EC — electrical conductivity, a proxy for total dissolved nutrients. Low EC (0.8–1.2) suits seedlings and leafy greens; high EC (1.8–3.5) suits fruiting crops.
- DLI — Daily Light Integral, the total daily usable light. Drives growth rate and, for fruiting crops, whether fruit sets at all.
- Days to harvest — first usable harvest from transplant unless noted; many leafy crops and herbs then crop continuously.
Crop parameter table
| Crop | pH | EC (mS/cm) | DLI (mol/m²/day) | Days to harvest |
|---|---|---|---|---|
| Aloe Vera | 5.5–6.5 (6.0 ideal) | 1.0–1.6 | 20–28 | 365+ (slow plant) |
| Amaranth Microgreen | 5.5–6.5 (6.0 ideal) | 0.4–1.0 | 12 | 10–14 |
| Arugula | 6.0–7.0 (6.5 ideal) | 0.8–1.4 | 12 | 21–40 |
| Basil | 5.5–6.5 (6.0 ideal) | 1.0–1.6 | 18–22 | 35–45 (first cut); months continuous |
| Beefsteak Tomato | 5.8–6.3 (6.0 ideal) | 1.8–3.0 (2.2 ideal) | 24+ | 100–140 (seed to first ripe) |
| Beet Microgreen | 5.5–6.5 (6.0 ideal) | 0.4–1.0 | 10–12 | 12–18 |
| Bell Pepper | 5.8–6.3 | 1.8–2.5 | 22–25 | 90–120 (seed to first ripe) |
| Bok Choy | 6.0–7.0 (6.5 ideal) | 1.5–2.5 | 14 | 40–55 |
| Buckwheat Microgreen | 5.5–6.5 (6.0 ideal) | 0.4–1.0 | 10–12 | 10–14 |
| Bush Beans | 5.8–6.3 (6.0 ideal) | 1.8–2.5 (2.0 ideal) | 20–24 | 55–65 (seed to first pods) |
| Butterhead Lettuce | 5.5–6.5 (6.0 ideal) | 0.8–1.4 | 13 | 28–40 (transplant) |
| Cherry Tomato | 5.8–6.3 | 2.0–3.5 (ramped) | 22–25 | 60–80 (transplant to first ripe) |
| Chives | 5.5–6.5 (6.0 ideal) | 1.0–1.6 | 18 | 40–60 (seed); 14 (division) |
| Cilantro | 6.5–6.7 | 1.3–1.8 | 12–14 | 30–50 |
| Cilantro Microgreen | 5.5–6.5 (6.0 ideal) | 0.4–1.0 | 10–12 | 18–25 |
| Cucumber | 5.5–6.0 | 1.7–2.5 | 20–25 | 50–70 (seed to first fruit) |
| Dill | 5.5–6.5 (6.0 ideal) | 1.0–1.6 | 18 | 40–60 |
| Eggplant | 5.8–6.3 (6.0 ideal) | 1.8–2.5 (2.2 ideal) | 22–28 | 90–120 (seed to first ripe) |
| Endive | 5.5–6.5 (6.0 ideal) | 0.8–1.4 | 11–13 | 45–55 |
| Hot Pepper | 5.8–6.3 (6.0 ideal) | 1.8–2.5 (2.0 ideal) | 22+ | 80–120 (seed to first ripe) |
| Iceberg Lettuce | 5.5–6.5 (6.0 ideal) | 0.8–1.4 | 13 | 45–60 (transplant) |
| Kale | 6.0–7.0 (6.5 ideal) | 1.5–2.0 | 14–16 | 25–30 (baby); 55–65 (full) |
| Lemon Balm | 5.5–6.5 (6.0 ideal) | 1.0–1.6 | 14–18 | 30 (cutting); 60 (seed) |
| Lemon Basil | 5.5–6.5 (6.0 ideal) | 1.0–1.6 | 18 | 40–60 (first cut); months continuous |
| Lettuce | 5.5–6.5 (6.0 ideal) | 0.8–1.2 | 14 | 28–35 (transplant) |
| Looseleaf Lettuce | 5.5–6.5 (6.0 ideal) | 0.8–1.4 | 13 | 25–30 (first cut) |
| Mache | 5.5–6.5 (6.0 ideal) | 0.8–1.4 | 11–13 | 50–60 |
| Marigold | 5.5–6.5 (6.0 ideal) | 1.0–1.6 | 14–18 | 60–75 (first flowers) |
| Microgreen Broccoli | 5.5–6.5 (6.0 ideal) | 0.4–1.0 | 10 | 10–14 |
| Microgreen Radish | 5.5–6.5 (6.0 ideal) | 0.4–1.0 | 10 | 7–10 |
| Mint | 5.5–6.5 (6.0 ideal) | 1.4–1.8 | 16–18 | 30 (cutting); 60+ (seed) |
| Mizuna | 5.5–6.5 (6.0 ideal) | 0.8–1.4 | 13 | 21 (baby leaf); 35–40 (full) |
| Mustard Greens | 5.5–6.5 (6.0 ideal) | 0.8–1.4 | 13 | 35–45 (full); 21 (baby leaf) |
| Mustard Microgreen | 5.5–6.5 (6.0 ideal) | 0.4–1.0 | 10 | 7–10 |
| Nasturtium | 5.5–6.5 (6.0 ideal) | 1.0–1.6 | 16 | 50–60 (first flowers) |
| Oregano | 5.5–6.5 (6.0 ideal) | 1.0–1.6 | 18–22 | 30 (cutting); 60+ (seed) |
| Pansy | 5.5–6.5 (6.0 ideal) | 1.0–1.6 | 12–16 | 60–80 (first flowers) |
| Parsley | 6.0–6.5 | 1.4–1.8 | 14 | 50–70 |
| Pea Shoots | 5.5–6.5 (6.0 ideal) | 0.4–1.0 | 10–12 | 12–18 |
| Peas | 5.8–6.3 (6.0 ideal) | 1.8–2.5 (2.0 ideal) | 18+ | 55–70 (seed to ripe pods) |
| Rosemary | 5.5–6.5 (6.0 ideal) | 1.0–1.6 | 20–25 | 60 (cutting); 120+ (seed) |
| Sage | 5.5–6.5 (6.0 ideal) | 1.0–1.6 | 18–22 | 60 (cutting); 90+ (seed) |
| Spearmint | 5.5–6.5 (6.0 ideal) | 1.0–1.6 | 14–18 | 30 (cutting); 60+ (seed) |
| Spinach | 6.0–7.0 (6.5 ideal) | 1.8–2.3 | 12–14 | 35–45 |
| Stevia | 5.5–6.5 (6.0 ideal) | 1.0–1.6 | 16–20 | 60 (cutting); 90+ (seed) |
| Strawberry | 5.5–6.5 (6.0 ideal) | 1.4–2.0 | 17–22 | 60–90 (transplant to first fruit) |
| Sunflower Microgreen | 5.5–6.5 (6.0 ideal) | 0.4–1.0 | 10–12 | 10–14 |
| Swiss Chard | 6.0–7.5 (6.5 ideal) | 1.8–2.3 | 14 | 50–60; then continuous |
| Tarragon | 5.5–6.5 (6.0 ideal) | 1.0–1.6 | 16–20 | 60–80 (rooted cutting) |
| Tatsoi | 5.5–6.5 (6.0 ideal) | 0.8–1.4 | 13 | 21 (baby); 40–45 (full) |
| Thai Basil | 5.5–6.5 (6.0 ideal) | 1.0–1.6 | 18 | 40–60 (first cut); months continuous |
| Thyme | 5.5–6.5 (6.0 ideal) | 1.0–1.6 | 18–22 | 45 (cutting); 90+ (seed) |
| Watercress | 5.5–6.5 (6.0 ideal) | 0.8–1.4 | 13 | 28–35 (transplant) |
| Wheatgrass | 5.5–6.5 (6.0 ideal) | 0.4–1.0 | 10–12 | 7–10 |
| Zucchini | 5.8–6.3 (6.0 ideal) | 1.8–2.5 (2.0 ideal) | 22+ | 50–60 (seed to first fruit) |
Grouping crops by reservoir compatibility
Plants that share a pH and EC band can run on the same reservoir. As a rule of thumb:
- Low EC (0.8–1.4), pH 5.5–6.5 — lettuces, most herbs, leafy brassicas, microgreens. The largest compatible group.
- Medium EC (1.4–1.8) — chard, kale, mature herbs, strawberries.
- High EC (1.8–3.5) — tomatoes, peppers, cucumbers, eggplant. Keep these on their own reservoir.
Mixing a low-EC leafy crop with a high-EC fruiting crop on one reservoir compromises both. When in doubt, group by the table above.
See also
FAQ
4 entries- Q01What pH and EC should I use for hydroponic lettuce?
- Lettuce targets pH 5.5–6.5 and EC 0.8–1.2 mS/cm at DLI 14. It is one of the most forgiving hydroponic crops. See the full chart below and the dedicated lettuce guide.
- Q02Which hydroponic crops need the highest EC?
- Fruiting crops sit highest — beefsteak and cherry tomatoes run EC 1.8–3.5 mS/cm, peppers and cucumbers 1.7–2.5. Leafy greens and most herbs stay between 0.8 and 1.6. The table lists every crop.
- Q03What is DLI and why does it differ by crop?
- DLI (Daily Light Integral) is the total usable light a plant receives per day, in mol/m²/day. Leafy greens thrive at 12–14, herbs at 14–22, and fruiting crops need 20+ to set and ripen fruit. Under-lighting is the most common cause of weak, stretched growth.
- Q04Where does this data come from?
- Each row is the target range published on that crop's own Rootless Farm guide, where the conditions are explained in context. Values are conservative working ranges for home and small commercial hydroponic setups, in metric units.