Grow Your Own Roast Dinner Vegetables – A Complete UK Guide for Gardeners
Introduction
Is there anything more satisfying than sitting down to a Sunday roast and knowing the vegetables on your plate came straight from your own garden? From crispy roast potatoes to sweet parsnips and earthy carrots, growing your own roast dinner vegetables is not only rewarding but also practical and delicious.
In this complete UK guide, you’ll learn how to grow your own roast dinner vegetables step-by-step, including the best varieties, sowing tips, companion planting advice, harvesting schedules, and storage methods. Whether you have a large allotment or a small raised bed, you can enjoy a homegrown feast from garden to table.
Why Grow Your Own Roast Dinner Veg?
- 🥔 Healthier and tastier – Nothing beats the flavour of fresh, homegrown veg
- 🌱 Budget-friendly – Grow large amounts from a packet of seeds
- 🪴 Flexible growing options – Grow in raised beds, containers, or allotments
- ❄️ Seasonal harvests – Plan for fresh or stored veg all autumn and winter
- 🌍 Sustainable eating – Reduce food miles and packaging waste
Essential Roast Dinner Vegetables to Grow
Here’s a classic line-up of UK roast dinner favourites and how to grow them:
| Vegetable | Time to Sow | Harvest Time | Notes |
|---|---|---|---|
| Potatoes | Mar–May | Jul–Oct | Choose varieties for roasting |
| Carrots | Mar–Jul | Jun–Nov | Long or chantenay types are best |
| Parsnips | Feb–Apr | Oct–Feb | Needs long growing season |
| Swede | Apr–Jun | Oct–Jan | Sweetens after frost |
| Brussels Sprouts | Mar–Apr | Nov–Feb | Classic winter brassica |
| Cabbage (Savoy) | Feb–May | Oct–Feb | Great for greens or slaw |
| Onions | Feb–Apr (sets) | Aug–Sept | Adds depth and sweetness to roasts |
| Garlic | Oct–Feb | Jun–Jul | Ideal for flavouring veg and meat |
| Rosemary | All year | All year | Perfect herb for roasties |
Pro tip: Stagger sowing dates to spread your harvest over autumn and winter.
Step-by-Step: How to Grow Roast Dinner Veg
🥔 1. Potatoes (The Roast Staple)
- Choose fluffy varieties for roasting such as Maris Piper, King Edward, or Desiree
- Chit seed potatoes in egg boxes before planting
- Plant 10–15cm deep in trenches or bags from March to May
- Earth up as they grow
- Harvest when foliage dies back, around July–October
Roast tip: Roast with garlic and rosemary for perfect crispy edges!
🥕 2. Carrots (Sweet and Earthy)
- Sow directly in light, sandy soil from March to July
- Thin seedlings to avoid overcrowding
- Protect from carrot root fly with fleece or companion planting (onions, leeks)
- Harvest when fingers-width thick, from June to November
Varieties to try: Autumn King 2, Nantes, or Chantenay Red Cored
🌰 3. Parsnips (The Winter Favourite)
- Sow early from February to April directly in well-prepared soil
- Germination can take 3+ weeks—be patient!
- Thin to 10–15cm spacing
- Harvest after the first frosts to sweeten the flavour
Varieties to try: Tender and True, Gladiator, or Javelin
🧄 4. Garlic (For Flavour)
- Plant October to February, using seed garlic cloves
- Space 15cm apart in well-drained soil
- Harvest when leaves start to yellow (June–July)
- Cure and store for months of roast-ready cloves
🧅 5. Onions (Sweet When Roasted)
- Use onion sets in spring for ease and reliability
- Plant March to April in firm soil
- Keep weed-free and water during dry spells
- Harvest when tops fall over and dry in August–September
🥬 6. Savoy Cabbage (For Steamed or Roasted Greens)
- Sow indoors in spring or direct in May
- Transplant to beds with 40–45cm spacing
- Water well and firm in
- Harvest from October to February
🧊 7. Brussels Sprouts (Love or Hate!)
- Sow in modules in March or April
- Transplant to firm ground with 60cm spacing
- Stake if needed in windy areas
- Harvest from the bottom up starting in November
🧅 8. Swede (Sweet, Nutty Mash)
- Sow direct in April–June
- Thin seedlings to 20cm apart
- Swedes prefer moist, firm soil and cool weather
- Harvest from October to January for best flavour
Roast tip: Swede is delicious roasted or mashed with butter and pepper.
Growing Roast Veg in Raised Beds or Containers
✅ Raised Beds
- Perfect for root crops (carrots, parsnips, swede)
- Use light, deep soil with added compost
- Easy to weed and harvest
✅ Containers
- Great for potatoes, herbs, onions, and carrots
- Use grow bags or pots 30cm+ deep
- Ensure drainage holes and use peat-free compost mixed with sand or perlite
Companion Planting for Roast Dinner Veg
| Main Crop | Good Companions | Benefits |
|---|---|---|
| Carrots | Onions, leeks, rosemary | Deters carrot fly |
| Parsnips | Chives, mint (in pots) | Reduces aphid attraction |
| Potatoes | Beans, brassicas | Beans fix nitrogen; brassicas deter pests |
| Onions | Lettuce, beetroot | Compact neighbours |
| Cabbage/Brussels | Nasturtiums, thyme | Trap crops for aphids and whitefly |
Avoid: Planting carrots near dill or coriander; potatoes near other nightshades (e.g. tomatoes)
Feeding and Watering Schedule
| Crop | Watering Needs | Feeding |
|---|---|---|
| Potatoes | Consistent, especially when tubers forming | General purpose feed every 2 weeks |
| Carrots/Parsnips | Light but regular | Avoid high nitrogen; enrich soil before sowing |
| Brassicas | Moderate | Feed with organic chicken manure pellets |
| Onions/Garlic | Low to moderate | Light feed at mid-growth stage |
| Swede | Moderate | Balanced fertiliser once or twice in season |
Protecting Your Crops from Pests
| Pest | Affected Veg | Solution |
|---|---|---|
| Carrot root fly | Carrots, parsnips | Use fleece or grow behind 50cm mesh barriers |
| Cabbage white butterflies | Cabbage, sprouts | Use netting, check for eggs, handpick caterpillars |
| Slugs and snails | Seedlings, leafy veg | Use beer traps, copper tape, or organic pellets |
| Onion fly | Onions | Rotate crops annually, grow under mesh |
| Aphids | Brassicas, carrots | Encourage ladybirds, spray with soapy water |
When to Harvest for a Roast Dinner Feast
| Veg | Ideal Harvest Time | Storage Tips |
|---|---|---|
| Potatoes | Jul–Oct | Store in paper sacks in a cool, dark place |
| Carrots | Jun–Nov | Keep in sand boxes or frost-free sheds |
| Parsnips | Oct–Feb (after frost) | Leave in ground or lift and store in sand |
| Swede | Oct–Jan | Harvest as needed; stores well in shed |
| Onions | Aug–Sept | Cure in sun and hang in nets |
| Garlic | Jun–Jul | Dry thoroughly and store in mesh bags |
| Brussels Sprouts | Nov–Feb | Harvest from bottom up as they mature |
| Cabbage (Savoy) | Oct–Feb | Harvest whole heads and store in cool area |
Add Flavour with Homegrown Herbs
Roast dinner isn’t complete without the aroma of fresh herbs. Here’s what to grow:
| Herb | Use | How to Grow |
|---|---|---|
| Rosemary | Roast potatoes, lamb | Evergreen shrub, full sun, well-drained soil |
| Thyme | Root veg, chicken, stuffing | Low-growing, drought-tolerant |
| Sage | Stuffing, pork, roast veg | Hardy, bushy, best in raised beds or pots |
| Bay | Stews, roasts, gravies | Grow in a pot or sunny spot |
Creating a Year-Round Roast Veg Garden
| Season | Key Tasks |
|---|---|
| Spring | Start sowing potatoes, carrots, onions |
| Summer | Feed, weed, and water regularly |
| Autumn | Harvest root veg, cure and store crops |
| Winter | Harvest hardy veg like sprouts and parsnips |
Conclusion
From sowing seeds in spring to roasting your harvest in autumn and winter, growing your own roast dinner vegetables is a practical, enjoyable, and delicious way to make the most of your garden or allotment. Even if you’re short on space, you can still grow many essentials in containers or raised beds.
By following this guide, you’ll be well on your way to plating up a hearty, homemade roast using your own veg—flavourful, seasonal, and 100% homegrown.
Top 10 Questions and Answers About Growing Roast Dinner Vegetables
1. Can I grow a full roast dinner in a small garden?
Yes! Use containers, raised beds, and succession planting to maximise space.
2. What’s the best potato variety for roasting?
Maris Piper and King Edward are UK favourites for fluffy roasties.
3. When should I plant carrots for a winter roast?
Sow June or July for harvests in October to December.
4. Do parsnips really taste better after frost?
Yes! Frost converts starches to sugar, improving flavour.
5. Can I grow roast veg in containers?
Absolutely—potatoes, carrots, garlic, onions, and herbs all grow well in pots.
6. What herbs are best with roast vegetables?
Rosemary, thyme, sage, and bay are top picks for roasting and seasoning.
7. How do I stop carrot root fly?
Use fine mesh netting or plant next to onions or leeks for natural deterrence.
8. When do I harvest swede and parsnips?
From October onwards—they get sweeter the longer they’re left in the ground.
9. Can I grow Brussels sprouts in windy gardens?
Yes, but stake tall plants and grow in firm, rich soil for best results.
10. How long does garlic take to grow?
Garlic takes around 6–9 months from planting to harvest.
Would you like a printable roast veg planting calendar, companion planting chart, or recipe sheet using your homegrown vegetables?