I have a conservatory and I am keen to start off veg from seed this season
? Which veg are appropriate
? When to start them
? Which dont do well from seedlings
Pretty well any veg can be grown from seed in a conservatory. However, carrots and especially parsnips don't like being transplanted and will grow best sown where they are to mature. Other roots (notably beetroot) are OK if sown in modules.
Don't start them too early. Although it's probably warmer in there than in an unheated greenhouse, there's not enough light till Feb/March (especially as the house is on one side) and they'll get tall and leggy. Follow the instructions on the seed packets as to the dates. If you do decide to start them early, try putting a reflective screen (a sheet of white or foil-covered card) on the house side of the seed tray.
Onions from sets are quicker than from seed, and you need so few plants of Brussels sprouts that it might be easier to buy them.
Broad beans are about the earliest to sow, sow in February in pots, to plant out when about 2" tall.
...and you can do the same with onion sets and beetroot.