Food & Cooking📅 2 April 2025⏱ 5 min read
How Long to Roast Vegetables: Times and Temperatures for Every Type
Roasting time depends on vegetable density, water content, and cut size. Here's a complete guide so every vegetable in the oven is ready at the right time — never mushy, never underdone.
JW
James WhitfieldPersonal Finance & Maths WriterJames has written about personal finance, health metrics, and everyday mathematics for over six years. He holds a BSc in Mathematics from the University of Leeds.
The most common roasting mistake is treating all vegetables the same. Dense root vegetables need 45 minutes; courgette becomes mush in 20. Here's a complete guide to getting everything right.
The Two Key Variables
Temperature: 200°C (fan 180°C) is the standard for most roasting. Higher temperatures (220°C/fan 200°C) give more colour and caramelisation; lower temperatures (180°C/fan 160°C) are gentler, better for vegetables that burn easily.
Cut size: Smaller pieces roast faster and develop more caramelised surface area. As a rule of thumb, every halving of size reduces cooking time by roughly 30%.
Roasting Times at 200°C / Fan 180°C
VegetablePrep / Cut SizeRoasting Time
BeetrootWhole (medium)50–60 min
Butternut squash3cm cubes35–45 min
CarrotsHalved lengthways30–35 min
Celeriac3cm cubes35–40 min
ParsnipsHalved or quartered30–35 min
Potatoes (roast)Parboiled, halved40–50 min
Sweet potato3cm cubes25–30 min
BroccoliFlorets15–20 min
CauliflowerFlorets or steaks20–25 min
Red / white onionsQuartered30–35 min
Cherry tomatoesWhole20–25 min
Bell peppersHalved or strips25–30 min
AsparagusWhole spears10–15 min
Courgette2cm rounds or batons15–20 min
Aubergine2cm cubes25–30 min
Brussels sproutsHalved20–25 min
Garlic (whole bulb)Top sliced off40–45 min (wrapped in foil)
LeeksHalved lengthways20–25 min
The Rules for Successful Roasting
Dry thoroughly: Water on vegetables steams them instead of roasting. Pat dry with kitchen paper after washing, and ensure they're fully dry before oiling.
Don't overcrowd: Vegetables touching each other trap steam. Use two trays if needed — a crowded tray produces soggy, not roasted, results.
Right amount of oil: Enough to coat each piece without pooling. Approximately 1 tablespoon per 400g of vegetables is a useful guideline.
Consistent sizing: Cut pieces to the same size so everything finishes at the same time.
Staggering Different Vegetables on One Tray
Planning a mixed tray:
Target finish at 45 minutes total
Add at 0 min (need 45+ min): parsnips, carrots, squash
Add at 10 min (need ~35 min): sweet potato
Add at 20 min (need ~25 min): peppers, onions
Add at 30 min (need ~15 min): broccoli, courgette, cherry tomatoes
Remove in order as each is done.