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First flowering

Record blackthorn first flowering when the petals of the first flower are open sufficiently for you to see inside the flower.

Expected Date Range: mid-February to mid-April  

Available historic data: we have good data from 1935-1939, and 1942-1954. We have some records from 1992-1998. 

Just right

  • (Kylie Harrison Mellor/WTML)

Too early

  • (Kylie Harrison Mellor/WTML)

Too late

  • (Kylie Harrison Mellor/WTML)
  • (Steven Kind/WTML)

Not to be confused with

  • Hawthorn (Crataegus monogyna). Blackthorn flowers before it leaves, whereas hawthorn will flower after it has its leaves (WTML).
  • Cherry plum (Prunus cerasifera). The sepals of cherry plum flowers are reflexed (i.e bent backwards, see red arrow), whereas the sepals of blackthorn flowers are not reflexed (see above image). Cherry plum flowers a few weeks earlier than blackthorn. Image credit: Helge Klaus Rieder