When To Fertilize Asparagus?

Last updated: 02/22/21

Asparagus is one vegetable I’ve always enjoyed because of its productivity rate. However, in my experience, I needed to fertilize it at the right time to get the best yield.

After careful research and a few years of trial & error, I want to present you with some useful information of when to fertilize asparagus.

Are you looking to understand when to fertilize asparagus? We’ve got you covered. In this article, I round up the main points of my research for you.

Dig in!

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When to Fertilize Asparagus

It would be best to get the fertilization done around early spring when the spears haven’t emerged. You can then fertilize around the month of June once you harvest. This will ensure your asparagus has the best nutrient supply for their growth and development.

However, the reality is that this act will depend on the stage at which your plant is. Now, we’ll tell you the fertilizer needs of your asparagus plant across the various stages of its growth.

This way, you can provide comprehensive care to them and meet their nutrient requirements.

Stages of Asparagus Growth

Now that you’ve got the general idea to keep in mind when fertilizing your asparagus, we’ll dive into the next relevant area. These are the stages of asparagus growth, and it is necessary to understand these stages.

This is to ensure that you can deliver the proper care required for a plentiful harvest. 

So, what do you need to know? Generally, the growth of asparagus takes two to three years after it is first planted. Note that these stages will also greatly influence the fertilization needs of your asparagus plant.

Now, pay attention to what you need to know about this crop.

fertilize asparagus best time

Soil Preparation

This is the first stage of asparagus growth. Generally, this stage requires you to prepare the asparagus bed, the soil where your asparagus will lie.

This is particularly important because of the length that the plant will spend on the bed – between ten to fifteen years, and sometimes as many as 20 years. The ground or soil quality becomes extremely important.

During this stage, you’ll want to provide soil will optimum nutrients. This way, you can record high yields. One way to do this is through composting. It provides nutrients to your soil and also increases your soil fertility. 

You can easily add a compost layer 2 inches deep if you’ve got a bed for 12 inches of soil or less. You can decide to go for either composted manure or standard manure.

Young Plants

The next stage of your asparagus’s growth is as a young plant. Generally, this involves the three years that follow when you plant it.

At this stage, you’ll need to fertilize the soil to ensure that your plant gets the required nutrient to grow great. It also ensures that your plants can get rooted properly.

So, you want to use a balanced fertilizer. As such, it must contain an equal amount of potassium, phosphorous, and nitrogen. Usually, you can use a 15-15-15 concentration or a 10-10-10 blend.

You’ll then do well with 2 pounds of this fertilizer for a space measuring 100 square feet. Do this during early spring or mid-spring.

Mature Plants

The next stage is when your plant gets matured. This is from the fourth year of your plant’s growth.

Generally, you’ll need to maintain the same amount of fertilization as we did when the plant was at its early stage. However, you’ll need to apply the fertilizers at a different time.

You’ll need to do that around late spring after your last harvest or in early summer. Also, it would be best to increase the nitrogen component of the fertilizer.

So, you could switch to a 5-10-5 fertilizer composition in favor of nitrogen. 

How to Grow and Care Asparagus Tips

Now that you’ve got the hang of fertilizing your asparagus, I’ll dive into the general care of your asparagus. You should know that this is as important as fertilizing your asparagus. This is because it will be difficult for you to get a great yield without an overall suitable condition.

So, here is some advice on how to grow and care for this crop.

1.Provide the Location with Access to Sunlight 

Access to sunlight is one thing that an asparagus needs for proper growth. In fact, this vegetable grows best under full sun. When you don’t provide adequate sunlight, you will only find yourself with weak plants and thin asparagus spears. As such, ensure that you provide your asparagus plants with sufficient sunlight. 

when to fertilize asparagus guide

2. Improve Your Soil Before Planting 

As you have seen, available soil nutrient plays a significant role in the growth of your asparagus. However, it would be best if you also concerned yourself with the overall health of your soil. This is thanks to the perennial nature of asparagus. 

So, ensure that you improve your asparagus bed before planting. You want to keep its pH level between 6.5 and 7.0 – the neutral range. You can confirm the soil type and pH type through soil testing.

Even more, asparagus enjoy phosphorus. So, you want to prioritize rock phosphate, bone meal, and composted manure during soil amendments. 

You also want well-drained soil. This is because whether you’ve got one-year-old asparagus plants or mature asparagus plants, they need well-drained, loose, fertile soil with nitrogen. However, remember that sandy, well-drained soil areas won’t do the trick. So, info on soil-state is vital.

3.     Watering

You also need to keep this vegetable watered regularly. This is even more important when they are young. Precisely, provide between 1 and 2 inches every week when it’s young to the soil surface. Then, you can reduce it to around 1-inch each week when it gets past two growing seasons. It’s never a bad idea to go for a soaker hose or an irrigation system. 

4.     Keep Within the Right Temperature 

You’ll also need to maintain the right humidity and temperature when growing asparagus. Generally, the appropriate soil temperature is between 70 and 85 and 60- and 70-degrees Fahrenheit in the day and at night, respectively. So, ensure that your soil temperature stays within the recommended limit.

5.      Manage Weeds and Pest

Weed growth is something you’ll have to manage for the best growth. So, ensure that you uproot weeds before planting. You should also monitor your asparagus patch every season to ensure that there’s no uprising of weeds. This way, through your weed control, your asparagus roots won’t have to compete for nutrients. You get healthy roots and a healthy crop.

For instance, you can use salt levels to discourage the growth of weeds in your bed. This is because asparagus can tolerate certain levels of salt. On the other hand, the weeds will find it hard to survive in your garden.

For pests and disease, while it’s not popular, the risk of fusarium wilt, needle blight remains. You cannot take asparagus rust and purple spot lightly. So, if your growing region experiences these diseases, you want to discourage their emergence through good sanitation.

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Final Thoughts 

One thing that made asparagus extremely attractive to everyone, including me, is its reliable harvest. Usually, you can enjoy as little as ten years and as much as 15 years of harvest when it comes to this option. 

However, the reality is that throughout this process, asparagus is known to drain the soil of its nutrients. To keep up with the nutrient needs, it’s not enough, to begin with, nutrient-rich soil. One must also fertilize the asparagus bed. 

In this article, we have addressed all that and fertilizer application. So, read up and learn when to fertilize your asparagus!

Related Questions 

Is Miracle Grow Good for Asparagus?

Yes, using Miracle Grow is a good choice for your asparagus growth. This is because asparagus requires considerable content requirement, and Miracle Grow helps to provide that.

What is the Best Fertilizer for Asparagus?

At the early stage of your asparagus growth, the best fertilizer is one that provides a balanced nutrient component of nitrogen, potassium, and phosphorus. Then, when your asparagus matures, the best option is one that contains high nitrogen content relative to the other nutrients.

Green Thumb Gardener
asparagus fertilizing guide
Jeremy Starke

We at Green Thumb Gardener provide tips and guides for both for beginners and advanced gardeners out there. 

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