Cold hardiness & minimum temperature

Is Matthiola incana 'Katz Sakura' (Matthiola incana 'Katz Sakura')cold hardy? Hardiness zone & min temp

Also called Katz Sakura Stock, Sakura Gillyflower.

More about matthiola incana 'katz sakura'

About Matthiola incana 'Katz Sakura'

Matthiola incana 'Katz Sakura' · also called Katz Sakura Stock, Sakura Gillyflower · flowering

'Katz Sakura' is a single-flowered, cut-flower stock bred in the Katz series for tall, straight, well-spaced spikes in soft cherry-blossom pink. Like all Matthiola incana it is a cool-season annual prized for its dense, clove-scented racemes. It performs best in cool, bright conditions and resents heat, which halts flowering and shortens vase life.

Cold limit: USDA 7-10 (grown as a cool-season annual; overwinters in mild zones) · RHS H3 (10-18°C)

Watch for — Bolting and flower collapse in heat: Temperatures above 18-21°C stop bud formation and cause spikes to fade fast; grow as an early-spring or autumn crop and avoid summer planting.

What matthiola incana 'katz sakura''s hardiness rating actually means

Hardiness works differently for matthiola incana 'katz sakura': it is grown as a seasonal crop, not overwintered. The question is not "what zone" but "how long is your frost-free growing window". Its RHS rating of H3 means: Half-hardy — comes through mild UK winters outside but is killed by a hard freeze. On the US scale that maps to USDA 7-10 (grown as a cool-season annual; overwinters in mild zones) — the zones where it can be left outdoors year-round.

New to these scales? The USDA hardiness zone map explained covers how the zone numbers work, and you can find your own zone with the zone finder.

Minimum temperature — and what happens below it

As an annual crop, its "minimum temperature" is the first hard frost — that is the end of the plant's life, not a survivable low. Many types are also damaged by light frost (around 0 °C).

Concretely, for matthiola incana 'katz sakura' as it gets too cold:

Light frost (around 0 to −2 °C) damages or kills tender summer crops outright; cold-hardy types take a few degrees of frost.
The plant does not "survive winter" — its life cycle simply ends, by design, when frost arrives or it finishes cropping.
A surprise late spring frost can also kill young transplants set out too early, before the season even starts.

Can matthiola incana 'katz sakura' go outside or overwinter — and where?

Time it to your frost dates: sow or plant out after the last spring frost, and aim to harvest before the first autumn frost.
In short-season zones, start it indoors or under cover to stretch the effective growing window.
Hardier crops in this group can be sown for an autumn or overwintered harvest in mild zones — check the specific crop.

Work back from your local frost dates with the frost-date calculator: the last spring frost and first autumn frost are what really decide when matthiola incana 'katz sakura' can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H3 figure above.

Frost protection for borderline matthiola incana 'katz sakura'

Matthiola incana 'Katz Sakura' is right on a hardiness edge in many gardens, so if you are pushing it, these measures buy it the margin it needs:

Use fleece, cloches or a cold frame at each end of the season to dodge a borderline frost and add growing weeks.
Have row cover ready for an unexpected late spring or early autumn frost.
Know your local last- and first-frost dates and count back the crop’s days-to-maturity to schedule the sowing.

Matthiola incana 'Katz Sakura' hardiness — frequently asked questions

Is matthiola incana 'katz sakura' cold hardy?

Hardiness works differently for matthiola incana 'katz sakura': it is grown as a seasonal crop, not overwintered. The question is not "what zone" but "how long is your frost-free growing window". A seasonal crop, not a perennial. Matthiola incana 'Katz Sakura' is grown 7-10 (grown as a cool-season annual; overwinters in mild zones); you sow after the last frost and harvest before the first one, then start again next year.

What is the minimum temperature matthiola incana 'katz sakura' can survive?

As an annual crop, its "minimum temperature" is the first hard frost — that is the end of the plant's life, not a survivable low. Many types are also damaged by light frost (around 0 °C).

What hardiness zone is matthiola incana 'katz sakura'?

Matthiola incana 'Katz Sakura' is rated USDA 7-10 (grown as a cool-season annual; overwinters in mild zones) and RHS H3 — Half-hardy — comes through mild UK winters outside but is killed by a hard freeze.

Can matthiola incana 'katz sakura' survive winter outside?

Time it to your frost dates: sow or plant out after the last spring frost, and aim to harvest before the first autumn frost. In short-season zones, start it indoors or under cover to stretch the effective growing window. Hardier crops in this group can be sown for an autumn or overwintered harvest in mild zones — check the specific crop.

How do I protect matthiola incana 'katz sakura' from frost?

Use fleece, cloches or a cold frame at each end of the season to dodge a borderline frost and add growing weeks. Have row cover ready for an unexpected late spring or early autumn frost. Know your local last- and first-frost dates and count back the crop’s days-to-maturity to schedule the sowing.