Asparagus officinalis is a perennial in the lily family and it lives for up to 30 years.
There are male and female Asparagus plants. The males have better quality spears and the females produce little red berries in autumn. The plants are not difficult to grow and will thrive under a variety of conditions. With proper care your asparagus bed should produce for 15 years or more.
Asparagus are heavy feeders and require a deep, friable, rich soil that is well prepared before planting.If you have a heavy, clay soil, you'll need to dig in plenty of gypsum and S.A Compost. Asparagus is very hungry and need plenty of organic matter such as cow manure, sheep manure, or such products as Rapid Raiser or Dynamic Lifter.
Asparagus can be grown by seed, or with seedlings. If you do grow them that way then after planting leave for about two or three years for a strong root system to develop. You must not pick any of the crop, just let it grow naturally.
The other way to grow them and usually the most popular method is buying a Asparagus crown, with its long fleshy roots. The crown of the Asparagus is where the spears will grow. Asparagus crowns are available for purchase and planting winter through to early spring starting from around May onwards.
To plant the crown you will need to dig hole or a trench if planting larger numbers. For each crown make a little mound, at the bottom of the hole/trench. Sit the roots of the crown nicely on top of the mound. Plant about 40cm apart. Water well once planted. Then in spring, little shoots will appear, at this time you can side and top dress with blood and bone. They can of course also been grown in very large pots .
When can I Harvest you ask? The crown and root system must be allowed to develop for one year before harvesting begins. Your may be tempted to do some harvesting the first year after planting, but bear in mind that removing spears will result in stress that will weaken your plants. Asparagus can be harvested for a 2- 3 week period the second year after planting. During the third, fourth and subsequent years, a full cutting season of 6 to 10 weeks are permissible.
It is not advisable to continue cutting well-established asparagus plants after the end of December in any year. During the cutting period, the plant draws on food reserves stored in the root system during the previous growing season. The top-growth must be allowed to develop after December in order to replace the food stores in the fleshy roots. Cutting is best done with a sharp knife that is pushed into the ground so that it severs the spear about 2 1/2 cm (1 in.) below ground.
Apart from slugs and snails in spring asparagus has very few pests and diseases.
Once the plants are around the 3 to 4 years old you should find they go yellow in autumn and that's the time to cut them back to ground level. The Asparagus bed will be bare until spring, and then those lovely spears of Asparagus will pop up back up in your garden.
Asparagus is high in potassium, great for fibre, low in salt, and a terrific, healthy vegetable to grow. There is nothing nicer than growing your own crop and taking it fresh to the table.