Death is always close. Milton said: “Death ready stands to interpose his dart.”
Nobody in his right mind wants to be reminded continually of this ominous truth. It feels particularly inappropriate when the sun shines on the birds rejoicing in full voice over the flowers.
Annual herbs have only young, fresh parts; short memories understandable. Viewing each other, consensus is easily gained that life is eternal. For them the death concept is reserved for later in the same season. If you will allow a little personification.
Protea glabra works differently: A durable shrub growing large over several years in arid conditions, retains its symbols of past sacrifices on the body. Dead branches persist among booming new growth, reminding of the hard grind seasons, if you live long enough.
Good to see that plant world also has those with a sense of history.