How To Identify Biennials and Perennials

(St Paul, MN)

I've just moved into a house that had beautiful and plentiful black eyed susan's. I'm reading that these are biennials or short lived perennials. How will I know if they will come back next season?

Doug says you'll know when they come back next season. :) If the mother plant dies off - but a bunch of babies around it spring to life -you have either of the above two options.

If a biennial, the new plants won't bloom in their first year.

If a short-lived perennial, the new plants will likely bloom in their first year but not necessarily. If they bloom for two years or more - then they're short lived.

Bottom line? There are annual, biennial, short-lived and reasonably long-lived forms of this plant. The only one you'll lose entirely in any garden year are the annuals in MN. (too cold for the seed to survive). The others will likely self-sow like crazy and become a weed for you.

Only a crazed gardener like myself really cares whether they're biennial or perennial when they just keep on multiplying and blooming.

The practical implication is that when the mother plant dies, you have to either move a baby into that space or fill it with something else. And that's the real "problem" here - keeping the garden filled up and blooming. Often the babies will be so close so they'll fill in the space after a year or two but you can speed that up by digging and moving larger plants into the spaces created by dying mother plants.

That's probably as clear as mud :-) You'll understand next spring when you see the plants start to grow (or not)

Enjoy them in any case.