Watering schedule

How often to water Spreading Spike Moss (Selaginella kraussiana) — the schedule

Also called Krauss's Spike Moss, Mat Spikemoss, Trailing Spike Moss.

More about spreading spike moss

Watering at a glance

Base rhythm	Keep soil consistently moist; check every 2-3 days
Spring / summer	Spring and summer: water when the top of the soil is dry to roughly a knuckle deep — typically every 2-3 days.
Autumn	Autumn: growth slows, so stretch the interval and let it dry a little more between waterings.
Winter	Winter: water noticeably less — often half as often — because low light and dormancy slow water use right down.
Light	Medium indirect light (a couple of metres from a window)

About Spreading Spike Moss

Selaginella kraussiana · also called Krauss's Spike Moss, Mat Spikemoss · houseplant

Spreading Spike Moss is a fast-growing, mat-forming spike moss native to the Azores, Canary Islands, and parts of Africa, widely naturalised in many warm-temperate regions. Its bright emerald-green, moss-like foliage spreads readily across moist soil. Ideal for terrariums and humid shelves. Not toxic to cats and dogs.

Ideal humidity: 70-90%

Watch for — Browning and desiccation: The most common problem — caused by low humidity or drying out. Restore moisture promptly and increase ambient humidity.

The watering schedule, season by season

Spreading Spike Moss likes a soak-then-partly-dry rhythm — let the top of the soil dry before watering again, and never leave it standing in water. The base rhythm for spreading spike moss is keep soil consistently moist; check every 2-3 days, 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.

Spring & summer (active growth): Spring and summer: water when the top of the soil is dry to roughly a knuckle deep — typically every 2-3 days.
Autumn (slowing down): Autumn: growth slows, so stretch the interval and let it dry a little more between waterings.
Winter (rest / dormancy): Winter: water noticeably less — often half as often — because low light and dormancy slow water use right down.

Selaginella kraussiana requires constant moisture and will rapidly wilt and brown if allowed to dry out. Water gently but frequently, keeping the growing medium just moist. Avoid puddling water on the foliage to reduce disease risk.

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 spreading spike moss in seconds.

How to tell spreading spike moss needs water

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

The top 2-3 cm of soil is dry to the touch (or a knuckle-deep finger test comes back dry).
Lifting the pot, it feels distinctly light.
Leaves droop slightly or lose a little of their gloss just before they truly need water.

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 spreading spike moss for a day is almost always safer than over-watering it.

Overwatering vs underwatering spreading spike moss

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

Signs you are overwatering

Yellowing lower leaves and a pot that stays wet and heavy for days.
Soft, brown, mushy stems or a sour soil smell — root rot.
Fungus gnats breeding in permanently damp soil.

Signs you are underwatering

Drooping, curling leaves with crispy brown edges that perk up after watering.
The rootball shrinks away from the pot and water runs straight down the sides.
Slow growth and a generally tired, washed-out look.

Watering spreading spike moss on a fixed weekly calendar regardless of season is the most common mistake — in dim winter light the same routine drowns it. Check the soil, not the date.

Water quality notes

Tap water is generally fine for spreading spike moss. If your water is very hard and you see brown leaf tips, switch to filtered or rainwater.

Seasonal and environmental adjusters

Every figure above shifts with the conditions in your home. For spreading spike moss, the levers that matter most are:

More light and warmth speed drying; the brighter the spot, the shorter the real interval.
Pot size and material matter — small terracotta pots dry far faster than large glazed or plastic ones.
Lifting the pot to feel its weight is more reliable than any calendar for judging when to water.

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 spreading spike moss.

Spreading Spike Moss watering — frequently asked questions

How often should I water spreading spike moss?

Water spreading spike moss keep soil consistently moist; check every 2-3 days. Spring and summer: water when the top of the soil is dry to roughly a knuckle deep — typically every 2-3 days. Winter: water noticeably less — often half as often — because low light and dormancy slow water use right down.

How do I know when spreading spike moss needs water?

The top 2-3 cm of soil is dry to the touch (or a knuckle-deep finger test comes back dry). Lifting the pot, it feels distinctly light. Leaves droop slightly or lose a little of their gloss just before they truly need water. The single most reliable test for spreading spike moss is the first signal on that list — checking the soil or the plant directly always beats watering by the calendar.

What does an overwatered spreading spike moss look like?

Yellowing lower leaves and a pot that stays wet and heavy for days. Soft, brown, mushy stems or a sour soil smell — root rot. Fungus gnats breeding in permanently damp soil. Watering spreading spike moss on a fixed weekly calendar regardless of season is the most common mistake — in dim winter light the same routine drowns it. Check the soil, not the date.

What are the signs of an underwatered spreading spike moss?

Drooping, curling leaves with crispy brown edges that perk up after watering. The rootball shrinks away from the pot and water runs straight down the sides. Slow growth and a generally tired, washed-out look.

Can I use tap water on spreading spike moss?