Plant Watering Schedule Calculator
Create a personalized watering schedule for your houseplants.
Enter plant type, pot size, and season to get a custom weekly watering calendar for each plant.
A plant watering schedule calculates how often and how much to water based on plant type, pot size, soil type, light exposure, and environmental conditions. Overwatering is the leading cause of houseplant death; underwatering is far easier to recover from.
Core formula: Watering Frequency = Base Interval × Environment Modifier × Season Modifier
Water volume per watering: Water Amount = Pot Volume × 0.25 to 0.33 (Rule: water until 25–33% of water drains out the bottom — this ensures root zone saturation without waterlogging)
What each variable means:
- Base Interval — default days between waterings for a given plant type under standard indoor conditions (medium light, 70°F, moderate humidity).
- Environment Modifier — adjusts for high heat/light (water more often) or low light/cool temps (water less often).
- Season Modifier — most plants need 25–50% less water in winter when growth slows; significantly more in summer.
- Pot Volume — a 6-inch pot holds approximately 1 quart; an 8-inch pot holds about 0.5 gallon; a 10-inch pot holds about 1 gallon.
Base watering intervals by plant type:
| Plant Type | Base Interval | Notes |
|---|---|---|
| Succulents / Cacti | 14–21 days | Let soil dry completely |
| Snake plant / ZZ plant | 10–14 days | Drought tolerant |
| Tropical foliage (Pothos, Philodendron) | 7–10 days | Keep slightly moist |
| Ferns / Peace Lily | 5–7 days | Prefer consistently moist soil |
| Fiddle Leaf Fig | 7–10 days | Sensitive to overwatering |
| Orchids | 7 days | Water, then let drain fully |
| Outdoor garden (established) | 3–7 days | Depends on rainfall |
Worked example: A Pothos in a 6-inch pot (1 quart capacity) in a bright indoor room during summer.
Base interval: 7–10 days → use 7 days for summer (warm, active growth) Water amount: 1 quart × 0.30 = 0.3 quarts (~300 mL per watering)
In winter: adjust to 10–14 days; reduce volume to ~200 mL.
Soil dry test: Insert finger 2 inches into soil. If dry at that depth → water now. If moist → wait 2–3 more days. This finger test is always more reliable than a rigid calendar schedule.