When to sow forget-me-nots in Shanghai

Why these dates

Sow in early summer, six weeks after the last frost, and move the seedlings in autumn to wherever the spring bulbs are planted. Flowers the following April and May, then pull the plants out as they brown and shake them over the bed to sow next year's crop.

Hardy to about -20C as a rosette. Needs a cold winter, and mildews badly in a humid summer, which is why it is best pulled as soon as flowering finishes.

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. Forget-me-nots are timed with planting out 20 weeks after it, and this page simply resolves those offsets against the frost date computed for Shanghai.

Hardiness is not the obstacle here. Shanghai is zone 9a, comfortably inside the range this crop is rated for, so an established plant should come through an average winter without protection.

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 Shanghai 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 Shanghai →