Cold hardiness & minimum temperature

Is Begonia 'Varsity Red' (Begonia semperflorens 'Varsity Red')cold hardy? Hardiness zone & min temp

Also called Varsity Red wax begonia.

More about begonia 'varsity red'

About Begonia 'Varsity Red'

Begonia semperflorens 'Varsity Red' · also called Varsity Red wax begonia · flowering

A vivid bedding wax begonia, 'Varsity Red' pairs deep bronze-green foliage with masses of single scarlet-red flowers from late spring until frost. Compact and uniform, it excels in mass plantings, borders and containers, shrugging off heat and tolerating part shade. It self-cleans, needs no deadheading, and can be overwintered as a houseplant.

Cold limit: USDA 10-11 (grown as an annual in zones 2-9) · RHS H2 (16-24°C)

What begonia 'varsity red''s hardiness rating actually means

Hardiness works differently for begonia 'varsity red': 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 H2 means: Tender — survives a frost-free greenhouse or a very mild, sheltered spot. On the US scale that maps to USDA 10-11 (grown as an annual in zones 2-9) — 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 begonia 'varsity red' 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 begonia 'varsity red' 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 begonia 'varsity red' can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H2 figure above.

Frost protection for borderline begonia 'varsity red'

Begonia 'Varsity Red' 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.

Begonia 'Varsity Red' hardiness — frequently asked questions

Is begonia 'varsity red' cold hardy?

Hardiness works differently for begonia 'varsity red': 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. Begonia 'Varsity Red' is grown 10-11 (grown as an annual in zones 2-9); you sow after the last frost and harvest before the first one, then start again next year.

What is the minimum temperature begonia 'varsity red' 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 begonia 'varsity red'?

Begonia 'Varsity Red' is rated USDA 10-11 (grown as an annual in zones 2-9) and RHS H2 — Tender — survives a frost-free greenhouse or a very mild, sheltered spot.

Can begonia 'varsity red' 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 begonia 'varsity red' 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.