1. In my raised garden, about 10 years ago I planted three asparagus roots (with deep [15 inch] trench and cow manure on the bottom). Up until 2017, the asparagus grew with healthy and thick stalks (size of middle finger), sprouting over 3-4 weeks, and produced thick beautiful ferns, 6-7 feet tall, after the picking season was completed, usually in April. However, in 2018, the asparagus stalks grew up thin and "spindly," most to no greater than 1/2 inch in diameter, perhaps the diameter of my small finger. The stalks that were left produced thinner ferns with a height about 50% of previous years. Over all the years I have never added any extra fertilizer. Question: How can I get back the strong production of healthy thick asparagus this Spring and, later, get tall. strong, thick ferns into the late Spring, and the summer?
Frederick County Maryland
There could be a few things, or a combination of factors going on here.
First off, the weather. Last season spring was late to arrive, and then many soils were inundated from the tremendous amount of rain we received. Asparagus needs well-draining soil, and if they don't have it, they will suffer.
Additionally, Asparagus is a hungry crop which needs a rich, organic soil. Being a medium heavy feeder, they are normally fertilized each season and often dressed with an inch or two of compost as well.
Here is our webpage on Asparagus for more information: https://extension.umd.edu/hgic/topics/asparagus
If your yields and plant health continue to go down, you might consider pulling one of the plants to investigate if the roots look blackened/diseased or compromised in any other way, for instance, chewed by rodents.