Guide to Growing Tomatoes in Adelaide

Written By:
Scott Carroll
Published On:
December 3, 2023

There’s something distinctly rewarding about biting into a juicy, ripe tomato you’ve grown with your hands. The burst of flavour is not just a treat for your taste buds; it’s the culmination of hard work, patience, and gardening wisdom. Here in Adelaide, our unique climate offers an excellent opportunity for growing tomatoes, provided we hit that sweet spot, knowing precisely when to plant and how to nurture these sun-loving plants. 

So, let’s embark on this red and luscious journey together as I share insights accumulated from years of gardening in this beautiful part of Australia.

Understanding the Climate in Adelaide

In Adelaide, we are blessed with a Mediterranean-type climate, which gives us warm, dry summers perfect for shorts—and equally important—for tomato growing! But understanding this climate is key to unlocking the secrets of successful cultivation. Generous sunshine during ripening leads to superior flavours; however, our relatively mild winters make timing our planting schedule paramount.

Tomato plants adore warmth but disdain frosty chills, which can spell disaster overnight. They require consistent temperatures between 20°C – 30°C for optimum fruit set. Fortunately for us Adelaidians, our conditions, more often than not, dole out this perfection during prime growing seasons.

Average temperatures and rainfall in different seasons

When considering when to plant tomatoes in Adelaide, one must respect the nuances each season brings:

  • Spring: Typically mild with average daytime temperatures ranging from 15°C to 20°C. This is when we start preparing soil beds and consider seed starting.
  • Summer: Hotter days will see averages climb up toward 28°C – perfect for bringing tomatoes to their full glory, but be cautious; extreme heat waves above 35°C can be stressful for plants without adequate care.
  • Autumn: As summer heat eases off into averages around 20°C -25°C in early autumn, it provides an extended chance for late-season varieties.
  • Winter: With cooler averages hitting below 16°C and increased precipitation, planting is usually off the cards unless protective practices like greenhouses or cloches are utilised.

The rainfall pattern shadow dances alongside these temperature shifts, typically lighter during spring (when irrigation is vital), progressing into heavier showers as winter approaches. Understanding these patterns creates a nurturing environment brimming with vibrant tomato life.

If your looking for more information on climate, check out our growing guide for Adelaide here.

Types of tomatoes that thrive in Adelaide’s climate

Finding the best tomatoes to grow in South Australia can be an exciting challenge and a deeply rewarding hobby for those of us with green thumbs and a passion for fresh, ripe tomatoes. The Mediterranean climate here in Adelaide, with its hot, dry summers and cool, sometimes wet winters, may not be ideal for every variety of tomato, but fret not – there are plenty that flourish.

Let me guide you through some tomato varieties that will not just survive but also thrive in our unique climate:

  1. Cherry tomatoes: Small yet flavorful, cherry tomatoes love the sun and heat, which Adelaide has plenty of. They start fruiting early and often continue until the first frost.
  2. Roma tomatoes: Roma or plum tomatoes are robust and excellent for making sauce or paste. They’re a determinate type of tomato plant, which means they’ll produce most of their fruit at once.
  3. Beefsteak tomatoes: These large-fruited tomatoes can do surprisingly well if given enough water to prevent stress during those scorching hot days.

When planning your garden, choose varieties revered for their heat tolerance and disease resistance; this will ensure they have the best chance to prosper under our blazing sun and occasional humid spells.

When to Plant Tomatoes in Adelaide

In Adelaide, the ideal time to plant tomatoes is from late August to early October in spring and in late summer (February) for an autumn crop.

Still, every year can bring its quirks with the weather. Henceforth, monitoring local forecasts and adapting your planting schedule is always wise.

When is it too late to plant tomatoes in Adelaide?

While enthusiasm can run high all season long, there comes a time when planting tomatoes might do more harm than good. Here are telltale signs that suggest it might be too late:

  1. Shortening days: As daylight hours dwindle entering mid-autumn (April-May), tomato plants will struggle with less sunlight, leading to poor fruit development.
  2. Cooler temperatures: Nighttime temperatures consistently below 10°C impede growth; if jackets are out of storage, hold off on tomato seeds.
  3. Crowded garden centres: This tends not only to indicate peak season has passed but also to indicate reduced availability of healthy seedlings, reflecting dwindling demand due to suboptimal conditions.

Recognising these signs helps prevent wasted effort while protecting remaining plants against potential drawbacks like fungus promoted by cooler temps.

Strategies for extending the growing season

Squeezing every possibility from Adelaide’s growing seasons means getting creative. Implementing strategies that defy cold snaps or scorching heat can remarkably extend your planting time frame:

  1. Use greenhouses or clear plastic covers: These protect plants from chilly winds and frost, allowing an earlier start and later finish.
  2. Lay down black plastic mulch: It absorbs sunlight, warming up soil pre-season. Just remember to use irrigation, as this mulch retains heat!
  3. Consider pot cultivation: Pots can move indoors during chillier nights, enhancing protection, which becomes pivotal as winter nears, offering another layer of flexibility regarding timing.

Deploying these methods judiciously gives tomatoes extra weeks they otherwise wouldn’t have under open skies, thus broadening horizons for eager growers in our sunny-yet-sometimes-surprising city of Adelaide.

Preparing the soil and site for planting

  • Tomatoes are quite adaptable but do best in well-draining soil rich in organic matter. You’re aiming for loamy soil, a balanced mix of sand, silt, and clay. This magical trio allows for good drainage while retaining enough moisture to nurture your plants. Let’s dial down into specifics:
  • Loose texture: Loosening the soil improves air circulation and allows roots to penetrate deeply.
  • Rich in organic content: Compost or well-rotted manure will boost the nutrient profile.
  • Slightly acidic pH: Tomatoes prefer a pH between 6.0 and 6.8.

Ensuring these conditions does take some work, but consider this groundwork as laying the foundation of a house, which is integral to its longevity.

Testing soil pH and making necessary adjustments

Knowing your garden’s soil pH is crucial because it influences how plants absorb nutrients. You can purchase an at-home testing kit from any local garden centre or send a sample to a laboratory for more detailed analysis.

If your soil is too acidic (pH below 6), apply lime to raise the pH. Conversely, if it’s too alkaline (pH above 6.8), you must add sulphur to lower it. Remember, changes in pH happen gradually over months – patience is truly a gardener’s virtue!

Once you’ve achieved that perfect piquant acidity akin to what tomatoes adore, maintenance becomes key—retest every couple of years to ensure your garden stays on track.

Preparing the planting site and addressing common soil issues in Adelaide

When prepping your tomato plot, aim to give these sun-lovers plenty of space for healthy growth; they’ll need around 60 centimetres between each plant and about a metre between rows.

Addressing common Adelaidean soil issues includes tackling the following:

  • Salinity: Given Adelaide’s geography, soils here can be saline, which hampers plant growth by affecting water uptake.
  • Compaction: Urban environs often mean compacted soils where root development struggles.
  • Nutrient deficiency: Phosphore can be low in native Australian soils yet vital for early root development.

Regular mulch applications protect against temperature extremes—an especially useful ally during those unpredictable Adelaide climes! 

With these tips under your belt—and perhaps some dirt on your hands, you’re already setting the stage for mouthwateringly juicy tomatoes come harvest time. 

Seed starting and transplanting tips

Starting tomato seeds indoors gives you a head start on the growing season. It allows for stronger, more controlled development of your young plants before they face the elements. 

Some general recommendations I have when it comes to starting with growing seeds indoors:

  • Timing: In Adelaide, you’ll want to initiate seedling growth about 6-8 weeks before the average last frost date.
  • Growing medium: Opt for a light, fluffy, high-quality seed-starting mix and a perfect bed for tiny seeds to take root.
  • Planting depth: Plant your tomato seeds roughly 5mm deep in individual pots or trays.
  • Moisture and warmth: Keep the soil consistently moist (not waterlogged) and maintain a temperature around 18-21°C, critical for germination.
  • Light: After sprouting, provide plenty of light—about 14-16 hours per day—to prevent leggy growth.

By focusing on these essentials, you’re setting up little champs that are robust enough to eventually transition outside.

Timing and techniques for transplanting seedlings into the garden

Anticipation builds as those seedlings mature, but patience is key when shifting them outdoors:

  • Hardening off: This process entails introducing your plants gradually to outdoor conditions.
  • Stable weather: Only transplant after all danger of frost has passed, typically from late September through October in Adelaide.
  • Evening transplants: Plant in the evening or on cloudy days to reduce transplant shock.

The hardening-off can take about 7-10 days, where daily daylight exposure increases until they’re ready for continual nights out.

How to plant tomato seeds

If starting seeds outdoors directly in your garden beds, set your heart ablaze with thrill-seeking pleasure:

  1. Wait until soil temperatures consistently stay above 12°C before sowing seeds.
  2. Choose a sunny spot because tomatoes worship the sun like ancient solar deities!
  3. Sow two seeds per hole at about 5 mm depth, and space holes approximately 50 cm apart for indeterminate varieties; determinate types can be closer.

A quick note to thin weaker seedlings post-germination: yes, tough love is sometimes necessary in gardening!

Patience will be your ally here as direct sown seeds might sprout more leisurely than their coddled indoor cousins.

Caring for young tomato plants to ensure healthy growth

These baby greens need TLC (Tomato Loving Care):

  • Water: Provide consistent moisture; use mulch to help retain soil dampness without going overboard.
  • Nutrition: Fertilise with a balanced liquid feed every couple of weeks once true leaves have formed – think fine dining rather than fast food rush.
  • Temperature check: Evenings can still get chilly in early spring, so protect those youngsters with cloches or row covers if needed.

Remember, these tips aren’t just suggestions; they’re your map to treasure! With devotion and adherence to them, expect bountiful yields of juicy Adelaide-grown tomatoes ripe for the picking come summer!

Tips on maintaining tomatoes

Growing tomatoes in Adelaide can be fulfilling with the right maintenance strategies. Keeping your tomato plants happy involves consistent watering, regular fertilising, and proper staking methods. As I delve into these areas, I’ll transport you from beginner to proficient in no time.


The first essential element of maintaining Adelaide tomatoes is adequate water. Consistency is a rule of thumb; too much or too little can spell disaster for juicy fruits.

Some other general recommendations I have when it comes to watering your tomatoes:

  • Always water at the base of the plant to keep moisture away from the leaves and avoid disease.
  • Give your tomatoes about an inch (2.5 cm) of water per week, increasing this amount in extreme heat.
  • Utilise mulch to minimise evaporation and maintain soil moisture levels.

Remember that over-watering can dilute the flavour, and under-watering can lead to blossom-end rot or splitting fruits—balance is key.


Tomatoes are heavy feeders, so ensuring they get their fill of nutrients will lead to luscious yields.

Let’s break down how to feed your tomato garden:

  • Start with a slow-release fertiliser when planting.
  • Once blossoms appear, switch to a phosphorus-rich fertiliser every two weeks.
  • Be cautious with nitrogen; too much early on encourages leaf growth over fruit production.

By nurturing the roots with sufficient nutrients, we’re setting up our tomatoes for success above ground. Check out our review on the best tomato fertilisers here for specific product recommendations. 


  • Support systems are not merely functional—they’re crucial for healthy tomato plants. Here are some quick, useful tips you can take away with you when staking your tomatoes:
  • Stake early while the plant is young to prevent root damage later on.
  • Use soft ties like strips of fabric instead of wire twists, which can cut into growing stems.
  • Regularly check and adjust ties as your plant grows taller and broader.

An upright posture allows better air circulation around the plant. It lessens disease risks—not to mention it makes harvesting those red beauties much easier!

Managing common pests and diseases in Adelaide

Undeniably, pests and diseases are part of gardening life—but don’t let them deter you from growing robust Adelaide tomatoes! Recognising potential threats early will give you an upper hand in managing them effectively:

  • Aphids: These little sap-suckers love tender new growth but can be dislodged with a strong jet of water or controlled using organic insecticidal soap.
  • Whiteflies: Like aphids, whiteflies feast on plant juices but succumb readily to yellow sticky traps near affected plants.

As for diseases:

  • Blight: Characterised by dark spots on leaves or fruit, practising crop rotation mitigates its occurrence and removes affected foliage.
  • Mosaic virus: Look out for mottled leaves, they’re usually spread by insects. Hence, keeping those pests in check helps prevent mosaic virus transmission.

It’s truly satisfying when you see robust vines laden with bright edible jewels just waiting to be picked, and it all starts by giving those Adelaide tomatoes undivided attention through each stage. With a proper watering strategy with smart feeding disciplines and vigilant pest control measures, growing tomatoes in Adelaide suddenly becomes less challenging—and way more fun!

When to harvest your tomatoes

Knowing when to harvest your tomatoes can be a blend of art and science. I want you to have that same burst of pride I feel when my own homegrown tomatoes are ready for picking—perfectly ripened, juicy, and full of flavour:

  1. Colour: Watch your tomatoes transform from green to their respective colour, whether red, yellow or even purple! They’re usually ripe for the taking when they achieve a uniform hue with no green spots near the stem.
  2. Firmness: Give them a gentle squeeze; they should feel firm but not rock-hard. You’re looking for that slight give, which indicates peak ripeness.
  3. Size: Expect mature tomatoes to reach their expected size based on their variety. Cherry tomatoes will naturally be smaller than beefsteaks at maturity.
  4. Easy release: A ripe tomato often comes off the stem quite easily. If you have to yank or twist harshly, it might need more time on the plant.
  5. Taste test: Sometimes, nature knows best, and so does your palate! Taste-testing a few can guide you toward knowing when exactly each variety hits its stride in terms of flavour.

Harvest typically starts around midsummer and tapers off as cooler weather sneaks in. An average guide would suggest starting from late January through February or March for growers in Adelaide.

How to harvest tomatoes

Our aim here is twofold: harvesting our Adelaide tomatoes effectively while preserving both fruit quality and plant health for future yields:

  • Use scissors for pruning shears: Avoid pulling tomatoes directly by hand, which can damage both the fruit and the plant. Instead, snip them neatly at the stalk using clean scissors or pruning shears.
  • Handle with care: Rough handling can bruise these beauties; handle them gently as if juggling delicate orbs that hold within them sunsets captured through summer days.
  • Pick regularly: Check plants every couple of days during peak season—it encourages continued production and keeps pests from getting overly tempted by overripe treasures.

Now you’ve gathered these bountiful Adelaide-grown treasures, it’s truly something special seeing nature’s gifts nurtured from seedlings into delectable fruits cradled in your hands, bringing us to safeguarding this freshness through adept storage methods!

How to store tomatoes

When it comes to storage, not all tomatoes are created equal. The way I keep my homegrown gems might differ depending on the ripeness stage when picked. 

Here’s what works best for me:

  • Fully ripe tomatoes: They should be enjoyed as soon as possible! However, if you need to store them, keep them at room temperature, away from direct sunlight. A countertop out of sunlight or a pantry shelf often does the trick.
  • Almost ripe or breaker tomatoes: Those with a blush of colour can mature beautifully on a windowsill or counter away from direct sun. This slight warmth helps coax out their flavour without causing decay, which warmer temperatures might encourage.
  • Green tomatoes: Whether it’s the end of the season and frost threatens your crop before they’ve had a chance to redden up, or you simply enjoy fried green tomatoes, store these away from light in a cooler part of your house. A garage or basement can work well for this purpose.

Short-term vs long-term tomato storage strategies

Here are some pointers for keeping your tomatoes tasting home garden fresh, whether it’s for now or later:

  • Short-term (Few days to a week):
    • Keep ripe tomatoes stem-side down on a flat surface.
    • Avoid refrigerating them, as cold temperatures can negatively impact flavour and texture.
  • Long-term:
    • For keeping longer than a week, consider preserving techniques such as:
    • Canning, where tomatoes are processed and sealed in jars.
    • Making sauces or purees, which can then be frozen for future use.

By adhering closely to these storage guidelines, I typically maximise the enjoyment of every tomato grown in my Adelaide garden—preserving that summer-sweet flavour well beyond harvest time!


Final thoughts

In conclusion, the journey of growing tomatoes in Adelaide is a delightful blend of art and science, deeply rooted in understanding our unique Mediterranean climate. The key to success lies in timing our planting to harness our summers’ warmth and our winters’ gentleness. 

We can enjoy a bountiful harvest by choosing the right varieties, such as cherry, Roma, and beefsteak tomatoes, and employing strategies to extend the growing season. Remember, it’s not just about planting seeds; it’s about nurturing them with the right soil conditions, watering, and protection against pests and diseases. 

Harvesting these sun-kissed treasures reminds us of the joy and satisfaction of growing our own food. So, whether you’re a seasoned gardener or a curious beginner, embrace the adventure of tomato gardening in Adelaide and relish the taste of your homegrown, ripe tomatoes.

If you liked this guide, check out our other city specific tomato growing guides for Sydney, Perth or Melbourne!