Repotting guide

When & how to repot Yellow Whitlow Grass (Draba aizoides)

Also called Yellow Whitlow Grass, Alpine Whitlow Grass, Yellow Whitlowwort.

More about yellow whitlow grass

About Yellow Whitlow Grass

Draba aizoides · also called Yellow Whitlow Grass, Alpine Whitlow Grass · flowering

Draba aizoides is a compact, cushion-forming semi-evergreen perennial native to limestone rocks and scree in the mountains of central and southern Europe, from Wales to the Balkans. It thrives in full sun with sharply drained, gritty soil and is among the earliest rock garden plants to bloom, producing bright yellow flowers in February through April. The single most important care point is excellent drainage year-round — waterlogged soil, especially in winter, will kill the plant. Neither Draba aizoides nor the genus Draba appears on the ASPCA toxic or non-toxic plant list; as a Brassicaceae member it is not considered a significant toxicological risk, but classify as mildly-toxic out of caution since ASPCA data is absent.

Mature size: Up to 10 cm tall and 20–30 cm across.

How to tell yellow whitlow grass needs repotting

Repotting on a calendar is less reliable than reading the plant. For yellow whitlow grass, watch for these signs:

Roots growing out of the drainage holes, or the rootball lifting the plant proud of the rim.
Soil that has shrunk away from the pot sides and no longer holds water.
The pot is unstable because the plant has grown top-heavy.
Old, compacted, broken-down mix that stays wet too long — for a succulent that is a rot risk, so refresh it even if the pot size is fine.

For the underlying biology of a pot-bound root system and why it stalls a plant, see our guide to spotting and fixing a root-bound plant.

How often to repot yellow whitlow grass

Every 2–3 years, into bone-dry mix. Yellow Whitlow Grass's growth habit — cushion-forming, semi-evergreen perennial with tight rosettes of stiff, bristle-fringed leaves and upright flower scapes. — sets the pace. Draba aizoides is a compact, cushion-forming semi-evergreen perennial native to limestone rocks and scree in the mountains of central and southern Europe, from Wales to the Balkans. It thrives in full sun with sharply drained, gritty soil and is among the earliest rock garden plants to bloom, producing bright yellow flowers in February through April. The single most important care point is excellent drainage year-round — waterlogged soil, especially in winter, will kill the plant. Neither Draba aizoides nor the genus Draba appears on the ASPCA toxic or non-toxic plant list; as a Brassicaceae member it is not considered a significant toxicological risk, but classify as mildly-toxic out of caution since ASPCA data is absent.

What size pot to step yellow whitlow grass up to

Use a pot only one size up — or even the same pot with fresh gritty mix if the roots have room. Yellow Whitlow Grass stores water and rots in a large pot of slow-drying soil. A tight terracotta pot that dries fast is far safer than a generous plastic one. Never up-pot a succulent by several sizes.

Not sure of the exact diameter? Our pot size calculator takes the current pot and root spread and tells you the right next size — it deliberately recommends a single step up, never a big jump.

The best time of year to repot yellow whitlow grass

Spring or summer, while yellow whitlow grass is in active growth and warm, is best — roots recover fastest then, and the plant is not sitting in cool damp soil. Avoid repotting a succulent in winter dormancy.

Step-by-step: repotting yellow whitlow grass

Repot dry. Do not water yellow whitlow grass for several days first. Working with dry roots and dry mix dramatically lowers the rot risk for a succulent.
Pick a snug, fast-draining pot. Choose terracotta one size up at most, with a drainage hole. Have gritty gritty, sharply drained loam or sandy soil ready.
Tip it out and clean the roots. Slide the plant out, crumble off the old soil, and trim any black, mushy or dead roots with clean snips.
Pot into dry mix. Set yellow whitlow grass at its original depth in dry gritty mix, firming gently. Do not bury the stem deeper than it was.
Wait a week before watering. Leave it completely dry and out of harsh sun for about 7 days so any damaged roots callus. Only then water lightly.

Aftercare

Keep yellow whitlow grass completely dry and out of fierce sun for about a week so any nicked roots callus before they meet moisture; watering a freshly repotted succulent is the classic way to rot it. Then resume the normal lean, dry rhythm. Do not fertilise for about 3 weeks — fresh mix already carries nutrients and feeding freshly disturbed roots scorches them.

The right soil mix for yellow whitlow grass

Yellow Whitlow Grass wants gritty, sharply drained loam or sandy soil. Use a mix of equal parts loam and coarse grit or pea gravel; neutral to alkaline pH (6.5–8.0) is acceptable; heavy clay must be avoided. Always use fresh mix when you repot — reusing old, broken-down soil reintroduces the compaction and poor drainage you are repotting to fix.

Repotting yellow whitlow grass — frequently asked questions

How often should you repot yellow whitlow grass?

Every 2–3 years, into bone-dry mix for yellow whitlow grass. Repot yellow whitlow grass every 2–3 years into a snug pot of gritty, sharply drained loam or sandy soil, ideally in spring or summer. Let it sit in dry soil and do not water for about a week afterwards so any nicked roots can callus. Over-potting and watering straight away is what rots succulents.

What size pot does yellow whitlow grass need?

When is the best time of year to repot yellow whitlow grass?

Should you water yellow whitlow grass after repotting?

No — not straight away. Repot yellow whitlow grass into dry mix and wait about a week before the first watering so any damaged roots callus over. Watering a freshly repotted succulent is the single most common way to rot one.

Should you fertilise yellow whitlow grass after repotting?

Not immediately. Wait about 3 weeks after repotting yellow whitlow grass. Fresh mix already contains nutrients, and feeding freshly cut or disturbed roots burns them. Resume your normal feeding routine once you see new growth.