It’s what veggie gardeners dream of – and quite easily achieve. Grow fresh, home-grown Asparagus spears that would cost you a bomb in the shops, free to eat and enjoy every single spring! But as so many of you have asked, how does one grow Asparagus from seed in Australia? For that matter, why even grow from seed if you can get Asparagus crowns instead?
We give you the good news about how to grow Asparagus from seed in Australia. Uncover the hows, the whens and the whys you need to know before you get started with this rewarding perennial vegetable.
Why Grow Asparagus from Seed?
There are tons of really good reasons to grow Asparagus officinalis the way nature intended – from seeds! Let’s give them a quick run through!
It’s cheaper than buying crowns.
Asparagus crowns are expensive. You’ll end up with more plants (and more asparagus) for your buck if you start your plants from seeds instead of planting crowns.
It only takes a year longer to get your first crop.
Whether you grow from seeds or crowns, the first phase of asparagus growing is about patience. If you grow from crowns, you start harvesting in the second year.
If you grow from seeds, you’ll harvest from year three onwards, giving the root system time to get strong. That extra 12 months is time well spent as our following points will show.
You get male and female Asparagus plants too.
This is one of the biggest bonuses you get from seed-grown asparagus. Growers of asparagus crowns cull female plants because they aren’t as productive as the males.
But that means you can’t expect to get seeds, and seeds are what you use to grow even more asparagus. So, apart from costing less to get started, seed-grown asparagus also gives you a chance to gather seeds for free.
You get to see those pretty berries.
Let’s not forget that Asparagus is more than just a food crop. The ferny foliage is truly beautiful. It’s even more stunning when you get to enjoy the sight of asparagus plants sporting shiny red berries.
No females? No berries, and that’s a bit of a shame. OK, so you can’t eat the berries and female Asparagus plants produce fewer, thinner spears. We think that’s not too much of a big deal.
There’s less transplant stress.
You may have wondered why seed-grown asparagus is only a year behind in time to harvest compared to crowns. The answer is transplant stress. It’s a real setback for any plant and it can shorten its life expectancy too. Since Asparagus can bear for 20 years and sometimes more, it’s worth waiting that extra year for seed-grown plants.
Where Should You Grow Asparagus?
Asparagus needs space and good light. Full sun positions are best, but your plants will also tolerate light shade better than many other veggies.
Since they don’t really like a lot of root disturbance, devote an area specifically to asparagus plants. Or plant it in garden beds where you grow perennial ornamentals.
The soil should be rich in organic matter and well-drained. Overcome soil issues by including lots of compost. If you have heavy, clay soil that tends to be soggy, consider building up the beds a little to improve drainage.
Work a good dose of well-composted manure into the soil. It will help it to deliver more nutrients and it will improve the soil’s structure.
How to Grow Asparagus from Seed
When to sow Asparagus seed in Australia
Spring is the best time to start asparagus seed. I like to start mine in containers. If you can care for them well, plant them where they are to grow. That means faster development and absolutely no transplant shock.
If you get frost, choose a protected location or wait until you think the danger of frost has passed. Once they’re past their first growing season, they won’t mind it, but frost can wreak havoc on tender seedlings.
Which months to sow Asparagus seed in Australia
Need a rule of thumb guide for Asparagus sowing time? Here's the best time to sow Asparagus seed in Australia.
Cool climate: September to November. Beware frost!
Temperate and Subtropical climate: August to November
Tropical climate: March to October: Avoid the hottest part of the year.
Arid: September to November. Unfortunately, you shouldn’t use grey water for these babies. Use mulch to reduce water demand.
Pretreating Asparagus seed for better germination
Before you sow your seeds, soak them in water for a few hours or let them lie in water overnight to get them started. You can sow without soaking, but it reduces the time you’d otherwise have to spend waiting for those exciting green shoots to emerge.
Asparagus seed sowing depth
Plant your seeds about 1cm deep and 20 to 40cm apart. I’ve seen some recommendations for deeper planting, but your germination won’t be as good.
The soft young shoots have to grow so much more just to break through the soil’s surface. Until they do, the baby plant has to rely on the nutrients stored in the seed. If they run out, you’ll never see your seedlings!
Watering Asparagus seed and seedlings
Keep your seedling soil moist. Once the plants are up and growing, you can start reducing the frequency of watering, but for now, keep the soil moist.
Remember, the root emerges first and it hasn’t had time to grow very deep. With your seed-soaking triggering the germination process, you need to keep the ball rolling. Dry soil kills seedlings. At the same time, don’t let the soil be waterlogged all the time – that promotes root disease and rot.
Sounds tricky? Not really. Check your babies daily and feel the soil with your finger. If it feels like a squeezed out sponge, you don’t need to water just yet.
Transplanting Asparagus seedlings
If you start your seed in trays or pots, let the plants’ roots establish well before trying to transplant. If they’ve formed a nice, sturdy root-ball that doesn’t crumble, they will hardly notice the change of scene when you transplant them. Set them out about 20 to 40cm apart with about a metre between rows.
Culling Asparagus
As we’ve already mentioned, female Asparagus plants aren’t as productive as males. They still produce spears, but they tend to be skinnier.
About half your seedlings will turn into females – you’ll easily see the tell-tale red berries. Although they are pretty, and the seeds are good to have, you might want to cull down to about one third females. It’s really your call.
If you’re feeling sorry for your baby girls and you have enough space, leave your surplus females where they are. You can also move them to an area where you usually grow ornamentals. Hey, they’re pretty, right?
Harvesting Asparagus
Prepare for the harvest. Asparagus plants are dormant in winter. Once the leaves have yellowed, you can cut them off at the ground. Now, you start waiting for the new shoots to appear in the form of asparagus spears.
Asparagus plants are quite heavy feeders, so a top-dressing of organic fertiliser in late winter or spring will give them a boost.
Wait it out. A lot of people get over-excited and pick their asparagus too heavily when the plants are very young. I’ve heard of people getting edible asparagus from seed-grown plants in as little as two years. However, unless you’re a master-grower, it’s better to give them another year to develop a strong root reserve.
Once they’re three years old, you can start harvesting lightly. You do need to leave some spears to develop into leaves, so err on the side of caution – at least while your plants are young. In subsequent years, you can get away with picking a little more heavily. Snap the spears off by hand to get the tender, green shoots and head for the kitchen with your harvested spears – you’re in for a treat!
Want it white? If you’re eager to have white rather than green Asparagus, you need to exclude light from the emerging spears.
A thick layer of mulch (15-20cm) will do the trick. When you see the tips pushing through, you simply scratch away the mulch and harvest your white asparagus spears. We found this great video on White Asparagus Farming.
Is it Easy to Grow Asparagus in Australia?
Australia is an exporter of Asparagus. Most of it is grown in Victoria where Asparagus is in its element. Cooler winter temperatures help to boost productivity.
All the same, it’s even possible to raise a commercial crop in tropical conditions. The genetics of the chosen variety will have an impact here.
Asparagus Pests And Diseases in Australia
There’s good news here. Asparagus plants aren’t particularly prone to pests and diseases and you may never encounter issues. In fact, New South Wales Agriculture recommends it as a profitable crop for organic farmers. Your main concerns (if any ever arise) are likely to be thrips and Rutherglen Bug.
Thrips
Thrips are very tiny and hard to spot, but if your plants are affected, the spears will exhibit distorted growth. They’re very hard to get rid of. Some growers report that growing basil plants near Asparagus repels this insect. Our guess is that spraying with basil-infused water would also confuse thrips.
You can reduce the chances of a thrips infestation by growing your Asparagus far from members of the onion family since onion thrips are the top culprits. Good weed control will also be a help. If all else fails, insecticidal soaps can help to control thrips. You will likely have to spray two to three times per week to get them under control.
Rutherglen bug
Rutherglen bug is only a problem in years when they’re particularly successful. Weed control, especially removing Patersons Curse, will help to keep the bugs at bay.
Slugs and Snails
Slugs and snails can be an annoyance. Luckily, it’s a problem that’s easily solved. Sprinkle wood ash on the surface of the soil around, but not touching the plants. Snails and slugs won’t cross the ashy soil surface.
Fungal diseases
Finally there are a couple of diseases, including a type of rust, that have been known to affect Asparagus. Limit the chances of picking up this problem by keeping your plants well-spaced. Water your plants at soil level in the morning rather than the evening.
Our Recommended Asparagus Variety
In our search for the best asparagus variety for Australian conditions, we came across Asparagus UC157. The name comes from the lot number it was given during Asparagus-growing research at the University of California. At a guess, it was the 157th genetic variant they tried!
Whatever the reason for the name, you can safely assume that this is a relatively hassle-free plant. It produces heavily enough to be attractive to commercial growers and home gardeners alike. It’s also known for its heat tolerance – a big plus in some of the warmer parts of Australia!
There you have it: a helpful guide on how to grow Asparagus from seed in Australia. Are you ready to grow Asparagus in your home garden? There’s no time like the present! Visit our store and get started now.