Polyanthus in the tropics

[Farang9]

When I lived in Scotland, I regularly grew Barnhaven polyanthus from seed.  Then Barnhaven went out of business, and I retired here to sunny Phuket.
Now a new supplier of Barnhaven seed has appeared (in France) and I wonder if there is any chance I could get these plants to gerow under my conditions.  My main concern is the temperature for germination, which may be cooler than I can provide.  Has anyone any experience in this matter?

[Diane Whitehead]

I've never had to do anything fancy to germinate polyanthus.  I just
sow them when the seed is ripe in the summer, and they germinate
quite quickly.  We don't have hot summers - mid 20s, and 30 is rare.
I should think a shady spot would do well where you are.

That said, it was never a plant that I thought to try when I was living
in the tropics.  I assumed that summer-flowering plants would be most
successful, but even so, most of the ones I did try were eaten by giant
snails.

My polyanthus flowers out-of-season often, when the temperature drops
in late summer.  I've never had it flower when we were having normal
summer temperatures.

[Farang9]

According to Barnhaven, the optimum temp for germination is 12-15*C.  Our minimum night temp is around 24*C, and in the afternoons we often reach 35-37*C!
I have ordered a couple of packets of seed, and will try them in the shade house.  Will report when I see what happens.

[David Pilling]

I've seen the "Danova" strain of primula acaulis or primrose touted as better for warm conditions than others.

I vaguely recall the word "vernalisation" appearing, in other words a cold spell is needed for flowers.

Reading Richards book on primulas, they seem to have adapted to hot climates just not the species traditionally grown in the UK.