On May 4, 10:36 pm, Sat wrote:
On Apr 6, 6:08 pm, researcher wrote:

My sweet peas grew very well and flowered well but some started dying
out too soon. I have grown sweet peas for years but this is the first
time this is occurring. I am located along the coast in So. CA.

I'm running into the same problems in the same general area (SoCal
coast). I tried growing them last summer and they died but that was
because I had to go out of town for a few days and didn't water them.
I planted my current batch in early March when temperatures were in
the 60's and they grew very well and bloomed but are now almost
completely dead (despite keeping them well watered).

Hopefully someone can shed light on this.

When I lived in Long Beach, my grandmother always planted sweet peas.
She planted them in October, and by December, she always had many,
many flowers, So she boxed them up and sent them by air mail ( a long
time ago) to her relatives in Nebraska who were astounded by that
strange place called Southern California where you had flowers for
Christmas.
Get "Early Flowering" types that will bloom in winter's short days.
Spring/summer flowering types will not bloom until daylight is 15
hours or more, and by then it is too hot. Some "Spring Flowering"
types may work also. Forget the Summer bloomers.
Do as Andrew suggested and keep them deadheaded or they
will stop blooming.
good luck next fall
Emilie
NorCal