Asparagus is one of the first plants to emerge from the ground in spring. And it is only these new sprouts that are really edible. As the plant gets taller it gets too tough and woody to eat. It develops fern like leaves and sometimes make poisonous berries if the plant is female. In full growth it is impressively tall and many people do not recognize it as asparagus.
Asparagus comes in many different cultivations but most commonly they are grown as green or purple. White asparagus is just regular asparagus that had the new sprouts covered up and kept from sunlight while they grew.
I planted purple and green asparagus many years ago and left them to grow full each year for a few years. This year is the first time I have tried to harvest any sprouts. I purposely left the plants alone so the root system would be able to grow and strengthen. Now that they are established roots, the plant will provide sprouts for many springs to come.
Asparagus is really one of the easiest plants to grow. I started with some bare roots from the garden store and planted them in a shallow hole. From there they have taken care of them selves for many years. They are in a back corner of the garden that I did not have time to properly maintain until this year. They have competed with the weeds every year and they are still thriving. I clear the dead woody stalks every spring but the plant itself requires no effort from me at all. It has survived wet years, dry years, cool years, and hot years.