When it comes to the yield, if you plant 30 to 40 Asparagus plants, it can already feed around 2 to 4 people many course meals. It is best to plant Asparagus crowns during the spring season.
How to Grow Asparagus
Step 1 - Start the seeds about 12 to 14 weeks prior to the last frost. This is since Asparagus needs three years before it becomes established and fully productive. Just sow the seeds in 1 1/2-inch deep flats. Grow the seedlings until they reach 1 year old.
Step 2 - Find a spot for your Asparagus crowns. It should be under full sunlight but it can also tolerate partial shade. It also needs a well-drained soil as well as a pH of more than 6.0.
Step 3 - Loosen the soil. Make sure it is 8 to 10 in. deep. Add well-aged compost. Since Asparagus is grown from crowns, select the one-year old crowns which are well-rooted and are not dry.
Step 4 - Dig a furrow or trench about 10 inches wide and 10 -12 inches deep.
Step 5 - Place about 2 - 4 inch tall mounds of loose soil by the trench's bottom. Then, set the spacing of the crown in the trenches to about 18 to 28 inches apart. Next, evenly spread the crowns along the trench's bottom before you cover it with two more inches of soil.
Step 6 - Add some high nitrogen fertilizer (5-10-19) prior to the spears appearing in spring and another by the end of harvest.
Step 7 - When the spears start growing in spring, fill the trench, gradually, to the top. Keep them moist but not wet.
Things to Remember:
Asparagus beds should be well weeded.
Asparagus plants require a cold period for dormancy.
Root vegetables are not suitable companions for Asparagus plants. Good ones are parsley, basil and tomatoes.
Harvesting Asparagus can be done when they're already 3 years old or when they're fully developed. On the 3rd season, you need to cut the spears slightly below soil levels. While doing so, make sure you don't damage the spears that still hasn't emerged. When the spears have reached 8 - 10 inches tall, cut them to at least a diameter of a pencil. The best times for harvest are on the 3rd year for two weeks and then, 4th year plants for 4 weeks or up.
As soon as the buds start feathering out, you can't eat them anymore.