How to Grow Summer Vegetables

There’s plenty to grow for summer – from salad greens and lettuces to aubergines, tomatoes, beans, capsicum, courgettes, cucumbers and more.

Whether you’ve got a few pots on the deck, raised beds, or a full veggie patch, here’s how to make the most of it.

 

Selecting the Right Variety

·      The vegetables you plant, and when you plant them, will depend on your region and local climate.

·      Always choose varieties suited to your area for the best results. See our Regional Planting Guide below for popular summer vegetables and the best planting times around New Zealand.

 

Pots or Containers

·      You can grow plenty of summer vegetables in pots, especially with today’s compact varieties.

·      Try Asian greens - bok choy, choy sum and wong bok, leafy greens like spinach, kale, rocket, lettuces like Tom Thumb or Little Gem, dwarf beans or cherry tomatoes, capsicum, chillies, courgettes, cucumbers, and more.

 

Ideal Planting Conditions

Healthy soil or mix is the secret to a productive vegetable garden or container.

New gardens

·      Choose a north-facing spot that’s sheltered from strong winds, and make sure your soil is deep, loose, and free-draining.

·      Prepare your soil about one to two weeks before planting.

Existing gardens

·      Enrich the soil by lightly turning it over and working in fresh Daltons Garden Time™ Compost and Garden Time™ Vegetable Mix before replanting. This refreshes nutrients and improves soil structure.

Pots & Containers

·      For pots and containers, protect from strong winds and position in a sunny location – and always use a good quality potting mix - see the section below for more.

 

 

Prime Planting Time

·      For most parts of New Zealand, Labour Weekend (late October) is the traditional time to plant summer crops once the soil has warmed.

·      To get a head start, sow seeds indoors in trays in September, then transplant seedlings once frosts have passed (see our Daltons Growing from Seed Guide).

·      You can buy seedlings from your local garden centre and plant them straight into the garden.

Top Tip: Succession planting works well – sow quick growers like lettuce and radish every few weeks so you don’t end up with one big harvest.

 

Planting in the Garden

1. Add a generous layer of Daltons Garden Time™ Compost and dig it through to a depth of 1–1½ spade lengths to improve soil quality and help plants develop strong, healthy roots.
   
2. For an extra boost, mix in Garden Time™ Chicken & Sheep Pellets for a safe, natural nutrient source.
   
3. Allow enough space between plants for airflow and maintenance.
4. Mulch with Daltons Premium Mulch & Grow and water in well.
   Top Tip: Put in stakes or supports before planting so you don’t disturb the roots later.

 

Planting in Pots or Containers

Potting up new containers

1. Choose a container large enough for the plants you are growing for example, courgettes need a larger pot, and make sure it has good drainage holes.
   
2. Fill with Daltons Premium Potting Mix or Premium Outdoor Container Mix, specifically designed for container growing.
   
3. Plant seedlings at the same depth as in the punnet, firm gently, and water well.
   
4. Position in a sunny, north-facing spot out of strong wind.
   
5. Keep the mix evenly moist; mulch the surface to help lock in moisture.
   
6. If planting early, move pots to a sheltered spot overnight when frost is possible.

 

Refreshing existing pots

1. Remove spent plants and tip out old mix; shake off and discard old roots.
   
2. Top up with fresh Daltons Premium Potting Mix or Premium Outdoor Container Mix and blend through the remaining mix.
3. If reusing more of the existing mix, recharge it with Daltons Premium Vege & Herb Fertiliser or Garden Time™ Vegetable Fertiliser.
4. Replant, water in well, and return to a sunny, sheltered position.

 

Fertilising

·      Apply a side dressing of Daltons Garden Time™ Vegetable Fertiliser every 4–6 weeks, depending on crop type and watering frequency – some vegetables are heavy feeders and may need more.

·      Always water fertiliser in well.

 

Watering

·               From mid-January to early February, consistent watering becomes crucial.

·               Mulch generously with Daltons Premium Mulch & Grow to retain soil moisture.

·               Irregular watering can stress plants and cause them to bolt (go to seed). Keep soil evenly moist and increase watering during hot, dry spells.

·               To help plants handle heat stress, water with Daltons Garden Time™ Seafeed NPK every 7 days.

 

General Care and Maintenance

·      Space plants well for good airflow, easier weeding, and staking.

·      Keep your garden tidy by removing dead leaves and weeding regularly.

·      Watch for signs of stress such as wilting or yellow leaves, often caused by inconsistent watering or nutrient deficiency.

·      Support taller or heavier plants, like courgettes, with cages or stakes as they grow.

·      Rotate your crops each season to prevent disease build-up and maintain soil health – see our Crop Rotation Guide.

 

Harvesting

·      Pick little and often – regular harvesting keeps plants producing. Beans, courgettes, cucumbers, and lettuce all reward frequent picking.

·      Harvest in the cool of the morning before the day heats up.

·      Always use clean, sharp scissors or secateurs to avoid damaging plants or spreading disease.

·      Enjoy vegetables fresh for the best flavour, and freeze, preserve, or share any surplus.

 

Pests and Diseases

 

Powdery Mildew often shows up in late summer on courgettes, beans, pumpkins, and cucumbers.

·      Remove affected leaves promptly and dispose of them – don’t compost them, as that spreads spores.

·      Help prevent Powdery Mildew with a copper-based spray applied before mildew appears.

Slugs and snails can demolish seedlings overnight. Protect plants with pet- and child-safe pellets, beer traps, or barriers such as crushed shell, bark, or sawdust.

White butterfly / green caterpillar – watch for small white butterflies fluttering around the garden. They lay eggs that hatch into green caterpillars which chew through leaves.

·      Check the undersides of leaves regularly and remove eggs or caterpillars by hand.

·      Use fine netting or insect mesh to protect young plants, or apply a suitable biological spray if needed.

Companion planting: Marigolds and calendulas have a strong scent that helps deter pests.