I have some endive seeds (Endivia 'Crispum'), and I want to know the guidelines on how to grow them. Our weather has been sunny with temperatures reaching low 60's at night and low 90's during the day. I'd like to know the size container I need as seeds and then as plants.
Sow the seeds in an organic (non - soil) seed starting mix, in cell pots, preferably indoors. Keep moist. Within 2-3 weeks, the seeds should germinate, and you should keep them in a brightly lit area (sun is good, but not midday sun in your warm climate).
After they reach the 3 leaf stage, you can start lightly fertilizing. Soon they will be pot bound in the cell, at which point you can safely move them to the new planter without the root ball collapsing. Plant them in a much larger container (preferable with at least 3 cubic feet of potting soil in it), and keep moist there. Keep weeds down, and fertilize regularly with a balanced fertilizer (not as necessary in the ground).
You are in a warm climate where these can be tricky to bring to head without premature bolting. Keep the plants out of midday sun, don't let the soil dry out, make sure they have plenty of nitrogen... You basically want to spoil it in every way you can if it has one stressful thing (in this case the high temperature), because stress makes the plant want to flower/seed faster (bolt), and you want to put that off as long as possible.