How a plant drinks water
The root needs two things at once: water and air. Good soil is like a sponge: after watering, it holds water in the small pores and leaves air in the big ones. If it's always soaked, the pores fill with water and the root drowns; if it dries out completely, the root dehydrates.
Water goes up the plant and evaporates through the leaves (transpiration): with more heat, more light and a bigger plant, it drinks more.
When to water
There's no "every so many days": you water when it's needed.
In flowering and with heat it can be every 1 to 3 days; a seedling, every few days.
- Stick a finger in the soil: if the first 2 to 3 cm are dry, it's time.
- Lift the pot: dry, it weighs much less than just watered. With practice, weight is the best indicator.
How to water
Deeply and slowly, until a little water comes out the holes at the bottom (about 10 to 20 %). This way all the soil gets wet and no dry spots are left. Then it's left to dry quite a bit before the next watering: that wet-and-dry cycle makes the root grow looking for water. The water left in the saucer is thrown out.
It's best for the water to be at room temperature.
Too much and too little
Lack of water: the leaves droop soft, like a rag, and the soil pulls away from the edge. It recovers in hours after watering.
Too much water: the leaves droop but stiff, swollen and dark, curled like claws. It's more serious and more common: the new grower overwaters out of affection. It's not so much the amount in one watering, but watering often without letting it dry out.
Flush the soil
When too much fertilizer builds up (burnt tips), you water with a lot of water (2 or 3 times the size of the pot): the water running out the bottom carries the salts away. Then you have to let it dry out well.
▼ Cons
- Watering too often (with the soil still wet) drowns the roots
- If it stays drowned for more than 24 h, it adds stress and lowers health
🎮 Practice it in UnderGrow
The water bar is like a battery: it drops on its own and each watering adds 50 % to it. 100 % is well watered: in flowering in summer that watering lasts about 3 days. What goes over 100 % drains off by itself in ~2 h. What drowns is watering too often: 3 waterings with the water bar at 70 % or more, without letting it drop below 40 %, and the root goes without air for a day. If it stays drowned for more than 24 h, it adds stress and lowers health, more and more up to 96 h (it only costs you if it's drowned more than half of the time). Flushing the soil soaks it, lowers the nutrient bar 50 % and doesn't count as watering too often. Tap water has pH 7,4: with pH down, watering with corrected pH brings the root closer to pH 6,2 (halfway each time) and flushing leaves it at pH 6,2.
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