How often to water heartleaf philodendron

The interval

A heartleaf philodendron is watered about every 8 days in the growing season and about every 14 days in winter. Growing season means the warm, bright months from spring to early autumn, roughly March to September in the northern hemisphere and September to March in the southern. Winter is the cold, short-day part of your own year. NC State Extension says to keep the soil slightly moist and slow down on watering in winter, and the Royal Horticultural Society says to water moderately and less in low temperatures.

Check the top 3 to 4 cm of compost with a finger, and water when it is dry at that depth. Then lift the pot. The RHS notes that a drier pot feels lighter than a wet one, and in a small pot with a trailing plant the difference is easy to learn. This plant also gives you a third signal, because the thin leaves droop noticeably when it is thirsty and lift again within hours of a drink.

Water from the top until water runs from the drainage holes, wait ten minutes and empty the saucer. Use water at room temperature. The compost should end up slightly moist, never soaked. Humidity is medium for this plant, so it is happy in an ordinary room or a hall.

Overwatering is the real danger, and NC State Extension warns that root rot can occur in overly wet soil. The signs are yellowing lower leaves and a pot that stays dark for days. A thirsty philodendron droops across the whole plant, and a plant that has drooped once and recovered has lost nothing. A plant that stays limp after a drink, with the compost wet, points to roots that have already failed.

What is particular to this plant is that it forgives. It survives for long periods in low light, according to NC State Extension, and a droop is the mildest sort of warning, so the safest rule is to wait for the droop or a dry finger and then water well, rather than topping up on a schedule. The RHS gives 15 degrees as its minimum winter temperature for it.

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