Vegetable in Focus: Asparagus

Hi I’m Sammy,

Your Good Farm in-house nutritionist. Here to bring you essential information on nutrition, diet and permaculture gardening - in a bite size, easy to understand, science-backed way.

Who can feel the warmth in the air, smell the jasmine and sense that summer is around the corner? I can. And few vegetables announce the arrival of spring quite like asparagus.

Australian asparagus is at its best from September to November, making this the time to enjoy it while it is local and more abundant.

It is also one of our most nutrient-dense vegetables, up there with some cruciferous vegetables like broccoli, providing folate, vitamin K, carotenoids, vitamin C, fibre and protective plant compounds. But there is a catch. Once picked, it begins losing freshness remarkably quickly.

Fruit and vegetables remain alive after they are harvested. They continue to respire, using stored sugars and nutrients to stay alive. Some vegetables respire slowly and store well. Pumpkins, onions and cabbages can last for weeks or months under the right conditions. Asparagus sits at the opposite end of the scale. It has one of the highest respiration rates of any fresh vegetable, which is why it loses sweetness and tenderness so quickly after harvest.

I first read about this in Jo Robinson’s Eating on the Wild Side over a decade ago and found it fascinating. Nutrient density underpins how I approach food and what I encourage in my clients, readers and friends. Knowing how quickly some vegetables lose nutrients after harvest can make a significant difference to your overall nutrient intake. You can eat the same amount of plants, but by understanding this and making a few simple tweaks, gain more nutrition from the same foods. The shorter the journey from paddock to plate, the more nutrients may be retained, particularly in vegetables with a high respiration rate.

Stay tuned for a nutrient density directory soon.

Ditch the supermarkets for this vegetable, and plenty of others while you are at it. Head to your local farmers’ market, see my directory below, and find growers who harvested their asparagus the day before.

Look for firm, dark green, glossy spears with tightly closed tips and moist cut ends. Fresh spears may even squeak when rubbed together. Avoid bunches that look limp, wrinkled, woody or dried at the base. Once home, stand the spears upright in a jar with a little water, cover loosely and refrigerate. Eat them within a day or two, or better yet, that night.

Asparagus is grown from an underground crown, it needs around two years to establish, or three when grown from seed, before it is ready to harvest. Once established, spears can grow several centimetres a day and seemingly appear overnight. Those left unpicked develop into feathery ferns, returning energy to the crown for the following season. A healthy asparagus bed can produce each spring for well over a decade.

Knowing the backstory of our food gives us a greater appreciation for what ends up on our plate.

Not only is asparagus rich in nutrients, it is also a prebiotic, containing fibres such as inulin that feed our beneficial gut bacteria. These microbes, in turn, help support digestion, immune function, inflammation regulation and even communication between the gut and brain. The list is long, so look after those microbes!

Its protective phytonutrients include flavonoids and sulphur compounds that support the body’s antioxidant defences. Those sulphur compounds are also responsible for the distinctive smell some people notice in their urine after eating asparagus, although whether you detect it largely comes down to genetics.

A note on chemical use

Regular readers may feel like I am starting to sound like a broken record, but this is worth revisiting as we head into spring. Chemical use often increases as weeds, insects and fungal pressure return, while crops that commonly carry multiple residues, such as berries, become more available and more frequently eaten.

Conventional asparagus production can involve herbicides, insecticides and fungicides. Australia regulates which chemicals can be used and sets maximum residue limits. However, remaining below a legal limit is not the same as being grown without synthetic chemicals, nor does it fully address the mixture of residues we may consume across different foods.

Recent examples raise questions about whether regulations always keep pace with changing diets and emerging evidence. In 2025, independent testing found that some blueberries contained enough dimethoate for a 20-kilogram child to reach their acceptable daily intake after eating around 13 to 20 berries. Dimethoate was not removed from berry production altogether. Instead, growers were required to wait at least 14 days between spraying and harvesting. While this waiting period is intended to allow residues to decline, I do not find it particularly reassuring that the response was to extend the timeframe rather than remove the chemical altogether.

Then, in 2026, Australia allowed paraquat to remain in use under tighter restrictions after a review that took almost 30 years. Paraquat has been banned in more than 70 countries, including the United Kingdom, Switzerland, Sweden, South Korea and Brazil.

Research has associated exposure to some agricultural chemicals with neurological disease, developmental problems and certain cancers. Organophosphate insecticides such as dimethoate have been linked with poorer cognitive development in children, while studies have associated paraquat exposure with Parkinson’s disease, although that relationship remains disputed. Glyphosate, malathion and diazinon have also been classified as probably carcinogenic to humans.

Much of this research involves agricultural workers or people with higher exposure, so it cannot be directly applied to the small residues found on one serving of vegetables. But we do not eat one vegetable, once. We eat mixtures of foods, potentially containing different residues, repeatedly over many years.

For me, that is reason enough to take a precautionary approach. Buy organic when available and speak directly with growers about how their asparagus was produced, how pests and weeds were managed and when it was harvested.

Fresh asparagus needs very little preparation. Snap or trim away the woody base but avoid peeling away more than necessary. The lower ends can also be saved for stock rather than thrown out.

Asparagus can be steamed, sautéed, roasted, grilled or quickly blanched, or eaten raw. The key is not to overcook it. It should remain bright and retain a little bite.

Pairing it with a quality fat such as extra virgin olive oil, butter, eggs or cheese adds flavour but also improves the absorption of its fat-soluble carotenoids and vitamin K.

Lemony asparagus with eggs and parmesan

This makes am easy and delicious breakfast, lunch or side dish. The eggs add protein and healthy fats, turning asparagus into a more balanced and satisfying meal. Parmesan is also one of those ingredients, much like bacon or garlic, that instantly takes a dish up a notch.

Ingredients

2 bunches fresh asparagus, preferably local and organic
4 pasture-raised eggs
1 tablespoon butter or extra virgin olive oil
1 small garlic clove, finely chopped (let it rest for 10 minutes to allow the beneficial compounds to become heat stable)
Zest and juice of ½ lemon
A generous handful of freshly grated parmesan
Sea salt and black pepper
Fresh parsley, chives or dill

Method

Bring a saucepan of water to the boil and cook the eggs for six to seven minutes, depending on how soft you like the yolks. Transfer to cold water, peel and set aside.

Trim the woody ends from the asparagus. Heat the butter or olive oil in a frying pan, add the asparagus and cook until bright green and just tender.

Add the garlic and cook briefly. Finish with lemon zest (the most nutrient rich part of the fruit), a squeeze of juice, sea salt and black pepper.

Transfer the asparagus to a plate, halve the eggs over the top and finish with parmesan and fresh herbs.  Add another drizzle of olive oil or knob of butter. Voila!

Sydney farmers’ market directory

Wednesday

Mosman Farmers Market, Georges Heights: 8 am to 2 pm.

Thursday

Double Bay Market, Guilfoyle Park: 8 am to 2 pm.
Hornsby Organic Food Market, Hornsby Mall: 8 am to 2.30 pm.

Friday

The Beaches Farmers Market, North Narrabeen: 8 am to 1 pm.

Saturday

Carriageworks Farmers Market, Eveleigh: 8 am to 1 pm.
Orange Grove Market, Lilyfield: 8 am to 1 pm.
Bondi Farmers Market, Bondi Beach Public School: 9 am to 1 pm.
Kings Cross Market, Fitzroy Gardens: 8 am to 2 pm.
Oxford Street Farmers Market, Darlinghurst: 8 am to 2 pm.
Ramsgate Food Market, Ramsgate Beach: 8 am to 1 pm.
Northside Produce Market, North Sydney: 8 am to midday on the first and third Saturday of each month.

Sunday

Marrickville Organic Food Market, Addison Road Community Centre: 9 am to 3 pm.
Manly Fresh Produce Market, Sydney Road and Short Street Plaza: 8 am to 2 pm.
Mona Vale Market, Pittwater RSL: 8.30 am to 1 pm.
Seaforth Market, Ethel Street: 8 am to 12.30 pm.

Why Carriageworks is different

Some farmers’ markets allow stallholders to buy produce wholesale and resell it, which is fine however Carriageworks differs. Its market charter requires stallholders to be the farmers, growers or makers behind their products, although knowledgeable farm staff and approved neighbouring growers are also permitted.

The difference is choosing food with a clearer connection to the people who grew it, where it came from and how it was produced. You can speak directly to the grower, ask questions and often buy food with far less time between harvest and eating, which can mean better nutrient retention too. Hurray!

Whatever market you visit, ask a few simple questions: Did you grow this yourself? Where is your farm? When was it picked? How was it grown?

References

Robinson J. Eating on the Wild Side: The Missing Link to Optimum Health. Little, Brown and Company; 2013.

Australian Asparagus Council. About Australian Asparagus and Seasonal Availability.

University of California, Davis Postharvest Research and Extension Center. Asparagus: Postharvest Handling, Respiration and Storage.

Food Standards Australia New Zealand. Australian Food Composition Database.

Hamdi A, Viera-Alcaide I, Guillén-Bejarano R, et al. Asparagus fructans as emerging prebiotics. Foods. 2023;12:81.

ABC News. Pesticide Residues Detected in Fresh Berries Sold in Australia. 2025.

Australian Pesticides and Veterinary Medicines Authority. Suspension of Specific Dimethoate Products Used on Berries. 2025.

Australian Pesticides and Veterinary Medicines Authority. Final Review and Restrictions for Paraquat and Diquat Herbicides. 2026.

Muñoz-Quezada MT, Lucero BA, Barr DB, et al. Neurodevelopmental effects in children associated with exposure to organophosphate pesticides: a systematic review. NeuroToxicology. 2013;39:158–168.

International Agency for Research on Cancer. IARC Monographs Volume 112: Some Organophosphate Insecticides and Herbicides. 2017.