Growli

Watering schedule

How often to water King Sundew (Drosera regia) — the schedule

Also called king sundew, regal sundew.

More about king sundew

About King Sundew

Drosera regia · also called king sundew, regal sundew · houseplant

King sundew is the largest sundew, native to a single South African valley, with strap-like leaves to 70 cm tipped in glistening, insect-trapping mucilage. It demands bright light, pure water, a peat-sand carnivorous mix, and a winter cool rest. Feed it gnats, not fertiliser. A temperamental but spectacular carnivore.

Ideal humidity: 50-70%

Watch for — Mineral burn from tap water: Using tap or filtered (not RO/distilled) water makes leaf tips brown and the plant decline. Switch to rainwater, distilled or reverse-osmosis water only.

The watering schedule, season by season

King Sundew is a bog plant adapted to nutrient-poor wet ground — it must sit in a tray of pure water and must never get tap water or fertiliser. The base rhythm for king sundew is keep the pot standing in 1-2 cm of water at all times; top up before the tray runs dry, but the real interval moves with the season, the light and the pot — so treat the figures below as a starting point and always confirm with the plant itself.

Use only rainwater, distilled or reverse-osmosis water (under ~50 ppm TDS). Tap-water minerals build up and kill the roots. Tray-water the pot from below; never let the medium fully dry.

Want this turned into a live reminder that adjusts to your home and the weather? The Growli watering calculator takes your pot size, light and season and returns a starting interval for king sundew in seconds.

How to tell king sundew needs water

A calendar is the worst way to water king sundew. Check the plant and the soil instead — for this species, look for these signals in order:

The most reliable single check is the first one on that list. When two signals agree, water; when they disagree, wait a day and look again — under-watering king sundew for a day is almost always safer than over-watering it.

Overwatering vs underwatering king sundew

The two failure modes can look alike at a glance, so check the soil weight and wetness before you decide. For king sundew specifically:

Signs you are overwatering

Signs you are underwatering

Tap or bottled mineral water kills king sundew. Its roots cannot handle dissolved minerals — only rain, distilled, or reverse-osmosis water will do.

Water quality notes

Only rainwater, distilled or reverse-osmosis water — never tap, mineral or softened water. This is the single most important rule for king sundew.

Seasonal and environmental adjusters

Every figure above shifts with the conditions in your home. For king sundew, the levers that matter most are:

Pot choice is part of this too — work out the right size with the pot size calculator, since a pot that is too big stays wet long enough to rot the roots of king sundew.

King Sundew watering — frequently asked questions

How often should I water king sundew?

Water king sundew keep the pot standing in 1-2 cm of water at all times; top up before the tray runs dry. Spring and summer: keep the pot standing in 1-2 cm of distilled or rainwater at all times; top the tray up as it is taken up. Winter: keep just damp, not flooded — many temperate carnivores need a cool dormancy with far less water.

How do I know when king sundew needs water?

The tray has run dry (during active growth it should rarely be empty). The peat-based medium feels dry rather than wet. Traps or pitchers shrivel or fail to form. The single most reliable test for king sundew is the first signal on that list — checking the soil or the plant directly always beats watering by the calendar.

What does an overwatered king sundew look like?

Blackening traps or pitchers from stagnant, warm, mineral-laden water. Rotting crown if kept warm and flooded through winter dormancy. Tap or bottled mineral water kills king sundew. Its roots cannot handle dissolved minerals — only rain, distilled, or reverse-osmosis water will do.

What are the signs of an underwatered king sundew?

Traps go limp and brown; pitchers dry up. The medium dries out and the plant collapses quickly.

Can I use tap water on king sundew?

Only rainwater, distilled or reverse-osmosis water — never tap, mineral or softened water. This is the single most important rule for king sundew.

Keep reading