The fastest way to lose a Ruby Necklace is to love it to death with the watering can. This trailing succulent from South Africa's Eastern Cape shrugs off heat and long dry spells, yet it rots within weeks when someone waters it like a house fern. I killed three strands of my own one damp October, and every time the cause was the same: too much water and too little sun. Ruby Necklace is not difficult, just specific, and most advice treats it like a generic hanging succulent when it is really sun-hungry.

Where Ruby Necklace comes from

Othonna capensis earns the name Ruby Necklace from bead-like leaves on thin trailing stems that turn deep purple and red in strong light. It grows wild across the Eastern Cape of South Africa, spilling over rocky outcrops and dry scrub in full sun. This species sits in the Asteraceae family, the same group as daisies, and that link explains its habit: it grows fast, trails long, and wants more light than a windowsill succulent usually gets.

Wild plants cope with hot summers and cool dry winters, so they are built for bright light and sparse rain. Copy that light if you want the deep colour. Pale green, stretched strands mean the plant is starved of sun, not food.

What does Ruby Necklace need to thrive?

Most failures come from guessing. Ruby Necklace is easier once you fix three numbers.

1. Bright, near-direct light for the colour

Ruby Necklace earns its name only in bright light. Aim for 4 to 6 hours of direct or near-direct sun each day, or run a strong grow light 12 hours a day if your window is weak. I keep mine on a south-facing sill and it holds a wine-red colour through summer. Move it back from the glass in a fierce heatwave since leaf tips can scorch, but keep it out of dim corners.

Shade makes the stems stretch, the spacing between leaves widens, and the purple fades to a washed-out green. Stretched strands can reach 40cm before they look thin and leggy, and a trim is then the only fix.

2. Sparse water on a real interval

Water every 10 to 14 days through spring and summer, and cut that roughly in half in winter when growth slows. I water mine on a fixed Monday slot and skip a week if the soil still feels cool at 3cm deep. Leaves wrinkle slightly when thirsty and plump back within a day of a drink. Soak the pot until water runs from the drainage hole, then let it dry fully before the next round.

This approach is the opposite of the daily misting some guides suggest. Ruby Necklace stores water in those bead leaves, and a wet schedule drowns the roots. Mix 1 teaspoon per litre of cactus fertiliser once a month in the growing season and that is plenty.

3. Gritty, fast-draining soil

Use a mix of 2 parts cactus or succulent soil to 1 part pumice, and add coarse sand if your bagged mix feels heavy. Aim for a blend that sheds water in seconds. I repotted mine into this ratio last spring and the firmer strands were obvious within a month.

Pots matter as much as the mix. Unglazed terracotta pulls moisture from the root zone and suits this plant better than glazed ceramic, which stays wet. For a trailing plant a shallow wide pot beats a deep one, since the roots are shallow.

The one mistake that kills it

Overwatering on its own is risky, but the real killer is overwatering plus low light. Put the two together and the plant does exactly what you do not want: the nodes where leaves meet the stem sit in damp soil and cold shade, and rot from the inside out. Strands that look fine on Sunday turn into soft, black mush by Friday, and rot climbs toward the crown if you leave it.

Colour tells the same story. Dim, wet conditions drain the purple away into pale, floppy green growth that snaps where it should be firm, and feeding will not fix it. Light and a dry schedule are the fix, set before rot starts.

When a strand does go soft, do not wait for it to recover, because it will not. Cut a few centimetres above the soft spot with clean scissors and let the cut callous for a day. Healthy tops root in the same gritty mix, and you lose only the damaged length.

How long should the soil stay dry between waterings?

Dry-down is the single habit that keeps this plant alive. After you soak the pot, wait until the top 3cm of mix feels dry and the lower leaves just begin to wrinkle before you water again. Warm rooms need about every 10 to 14 days in summer, while a cool winter pushes the gap out to between 18 and 21 days. Keep the room between 60 and 75°F (16 and 24°C) and the pot on the dry side, and rot rarely starts.

Moisture meters help if you are unsure, but your finger at 3cm deep is honest enough. This plant forgives a missed week far more easily than a soggy one.

Quick care summary

Here is the whole routine in one place. Light: 4 to 6 hours of direct or near-direct sun, or a strong grow light for 12 hours. Water: every 10 to 14 days in the growing season and only after the soil dries at 3cm. Soil: 2 parts cactus mix to 1 part pumice in a shallow terracotta pot with a drainage hole. Strands trail 30 to 60cm in good conditions, so give it room to hang or spill. One rule overrides the rest: bright light and a dry schedule beat any fancy fertiliser or gadget.

If you want to branch out, Senecio rowleyanus (string of pearls) and Curio repens are close cousins with the same sunny, dry demands and a similar trailing look. These make a good shelf trio once you have the Ruby Necklace rhythm down.

Frequently Asked Questions

Q: Why are my Ruby Necklace leaves turning green instead of purple?

A: Almost always too little light. The red and purple pigments build up only under 4 to 6 hours of direct sun. Move the plant to a brighter sill or add a grow light, and the colour returns over a few weeks as new growth comes in.

Q: How long do Ruby Necklace strands get before they need a trim?

A: Good light gives strands 30 to 60cm. Once they get leggy with wide gaps between leaves, usually past 40cm, cut back to a node and root the tip. A light trim keeps the pot full instead of stringy.

Q: Can Ruby Necklace grow under a grow light with no window sun?

A: Yes, with a strong enough light. Run a full-spectrum grow light 12 hours a day about 15 to 30cm above the plant. Weak, distant lights give the same pale stretch you get from a dim window.

Ruby Necklace rewards the grower who treats it like the sun-loving South African it is, not a shade houseplant that wants constant drinks. Give it bright light, a gritty dry pot, and the patience to let the soil run dry, and those ruby strands will trail 30 to 60cm without fuss. For the bigger picture on keeping succulents happy, our complete succulent guide is the page I would read next.