Safe to Plant

Honesty · Taboão da Serra, São Paulo, Brazil

When to sow honesty in Taboão da Serra

Main outdoor window

not outdoors here

The window this page is built around.

Timed from last spring frost

no spring frost

In Taboão da Serra, on your chosen risk.

First autumn frost

no autumn frost

The far end of the outdoor season.

The average last frost. Half of all years are later than this.

Step by step in Taboão da Serra

Each window is a range, not a single day. Earlier in the range buys you a longer season; later in it buys you a safer one.

Frost tolerance
Very-hardy
Damaged below
-20°C (-4°F)
Days to flowering
300–340
Hardy to
Zone 4a–9a
Min soil temp
13°C (55.4°F)
Spacing
40 cm
Sowing depth
5 mm (0.2 in)
Sun
Partial

Honesty through the year

Against the frost risk in Taboão da Serra

Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Frost risk Today

Why these dates

Sow in early summer, six weeks after the last frost, in shade or part shade. Move to the final position in autumn. Flowers the following April, then sets the discs through summer; cut the stems when the pods turn beige and rub the brown outer skins off to reveal the silver.

Hardy to about -20C as a rosette and needs winter cold to flower. Tolerates dry shade under trees better than almost any other flowering biennial.

Seed packets and extension guides express timing as weeks either side of the last spring frost, because that is the only reference point that travels. Honesty are timed with planting out 20 weeks after it, and this page simply resolves those offsets against the frost date computed for Taboão da Serra.

Taboão da Serra sits in zone 10b, which is milder than this crop wants, and a winter that never really arrives is its own problem. The dates below still describe the right time of year; the open question is survival rather than timing.

This is a two-season crop, so the dates above describe a sowing in one year and a flowering in the next. The plant spends the winter in the ground as a small rosette, which is why the frost-free season in Taboão da Serra does not limit it the way it would limit a tomato: it is not trying to finish before the cold arrives, it is trying to be well enough rooted to sit through it. Sowing too late is the real risk, because a plant that goes into winter undersized often fails to flower at all the following year.

See every crop timed for Taboão da Serra →

Growing honesty in Taboão da Serra

How much frost will honesty tolerate?

Hardy to about -20C as a rosette and needs winter cold to flower. Tolerates dry shade under trees better than almost any other flowering biennial.