Sometimes the advice you are given can be a little outdated, or it can be qualified in a certain way. For example, like telling someone that to grow asparagus you need a lot of space and time. In a way it is true - particularly if you're looking to maximise your yields - but that doesn't mean that you can't grow it if you possess neither.
The truth is that with little space (even a medium/large pot will do) and in little time (in a matter of a month if grown from a mature crown) you can get your first home grown spear of asparagus. And just one is totally worth it!
Asparagus is one of those je ne sais quoi vegetables that evokes something special. Kind of like that perfectly incompatible partner that, despite the endless arguing and heart break, you just can't stop yourself seeing. Perhaps it's to do with its timing (the asparagus that is) - being exclusively the first harvest of spring - but if you thought that in-season asparagus was a flavour to behold, you need to try growing your own at home. It's next level.
For as long as we can remember, we've advised against growing it unless endowed with space and time. But more recently - ever since we popped in a couple of crowns in a veggie crate - we've had a change of heart. Even as a short term prospect (using nothing more than a pot) asparagus can quickly reward you with produce.
+ When to Plant
Cool/Mountainous (Hobart/Canberra): Oct-Jan
Temperate (Melbourne/Adelaide/Perth): Aug-Dec
Subtropical (Brisbane/Sydney): Jul-Dec
Tropical (Darwin/Cairns): Not suitable
+ Planting Info
Best grown from: Rhizome
Position: Full sun preferable
Depth: 5-10cm over the top of the rhizome
Spacing: 60 cm
Soil: dig in a lot of well-rotted manure, to a depth of 20cm, into a well draining soil. If growing in pots, use good quality potting mix.
Ideal pH level: 5.5 – 7.0
Best suited to: Pots, in-ground
Growing in pots: Minimum pot size 40cm, in width and depth
You can grow asparagus from seed - collected from the ferny growth of the female plant - but for a quicker harvest, it's best grown from a crown. A crown is a rhizome (mature root zone) that lies dormant in winter and re-sprouts once the soil temperature warms approaching spring.
Dig a trench/hole in the soil, and plant the rhizome with the roots hanging down, and the top of it 10cm underneath soil. Water in well.
Time until first harvest: this is where we used to say 2 years +, because the idea was to concentrate on bulking up the plant and letting the first spears turn ferny. So now it's your choice; you can harvest right away - which is about 2 months when growing from a crown - or you can follow the old principle.
How to harvest: Best to use a harvesting knife or snips, and cut shoot at (or a bit below) ground level and cover the cut ends with soil so they heal quickly. Depending on the sex of the plant, spears will be approximately 5-10mm in diameter, the female species producing more slender spears than the males.
At season's end: during early summer, spears will start turning woody and then you know the glory (for that year) is coming to its close. At this point allow the last spears to turn ferny, which will help bulk up the root matter for greater productivity next year.
Feeding: Regularly fertilise with seaweed extract to help develop the crowns for harvest. Feed the plant in autumn, before it's dormant period, with plenty of compost and well-rotted manure.
Mulching: to lock in the moisture and also to blanch the crowns, use a thick layer of mulch (lucerne hay, sugar cane or pea straw) - anywhere between 5 and 20cm - depending on how much of the stem you want to blanch.
Cut back: early winter, cut the plant back hard, to ground level and cover over with a little compost.
+ Potential Pest/Disease
Rats, if they can get to it; Aphids; Asparagus beetle; Crown rot