Harvesting, storing & cooking asparagus

Highly sought-after for its delicate flavour, the asparagus harvest is much awaited by gourmets and gardeners alike. Best eaten fresh, discover more about harvesting, storing and cooking asparagus.

Whether fried, steamed or baked, asparagus (Asparagus officinalis) has long been a prized kitchen ingredient. Read on to find out how to correctly harvest asparagus, the best ways of cooking it and how to store it if it cannot be eaten straight away.

When to harvest asparagus

Depending on the location and variety grown, the asparagus season arrives with spring and tends to begin around mid-April. With the harvesting season lasting for 8 weeks for established asparagus plants, you will want to enjoy your crop as much as possible before it needs to be left to recuperate until the following year. 

Planting and growing asparagus is an investment and as tempting as it is to want to harvest from newly planted asparagus crowns, it is important not to give in and pick the spears for the first 2 years, as the plants need to get established first. 3-year-old asparagus plants can be harvested sparingly from April for up to 6 weeks, but it is not until the 4th year that the plants can be harvested for the full 8 weeks or until the spear production declines.

As hard as it is to stop picking the delicious spear in June, it is important, as the asparagus crowns need to be allowed to build up their energy reserves to produce a good crop the following year.

How to harvest asparagus properly: the best way to cut asparagus

If you are wondering how to cut or harvest green or purple asparagus when the spears start appearing in April, the best way is to cut each spear with a sharp and clean knife 2.5cm below the soil’s surface. It is important not to cut any deeper than this, as it may damage the hidden crowns. Regular harvesting every 2 to 3 days so that the spears are no more than 18cm tall is recommended, especially when the weather is fair and the spears are growing well.

There are three main types of garden asparagus. Here in the UK, green and purple asparagus are the two most commonly grown varieties. However, white asparagus, which is not commonly grown here, is widely cultivated and highly prized for its flavour in other parts of Europe. Grown with the spears cultivated under the soil to prevent photosynthesis, white asparagus is harvested in a slightly different way.

To harvest white asparagus, locate the growing tips and carefully remove some of the surrounding soil. Insert the knife down alongside the spear and cut the spear at the base, before pulling up and backfilling the hole with soil.

Tip: asparagus can be grown either from seed or crowns, find out all about growing asparagus in our separate article.

Storing and preserving asparagus

Asparagus is best eaten as fresh as possible. However, there are times when this is not possible, and it will need to be stored in the best way to prevent it from drying out and losing its flavour. Once picked, green and purple asparagus spears are best stored in the fridge standing upright in water, whereas white asparagus is best wrapped before placing in the fridge.

Pickling your asparagus spears can preserve them for even longer and provides a great snacking option. To pickle the spears, trim them to fit a sterilised jar and submerge them with hot brine before adding the lid. Once cooled, the pickled spears can be stored in a fridge and will keep for up to 2 weeks.

Storing asparagus in the fridge

When storing unprepared asparagus in a fridge at around 4 to 5 °C it can keep for up to a week; although after 3 to 4 days it can start to turn slightly soft and become less flavoursome. To preserve green asparagus in the fridge, place it in a vase or large glass filled with 2 to 3cm of water to help prevent it from drying out. White asparagus, on the other hand, stores better when it is wrapped in a few sheets of damp paper towel or a damp tea towel.

Asparagus can also be frozen for longer periods up to 6 months. To freeze asparagus, blanch the spears in boiling water for 2 to 3 minutes before placing them in ice cold water. Allow to dry. The spears can then be frozen in an air-tight container until required.

Storing asparagus once it has been peeled

Peeling asparagus is not strictly necessary, although some recipes may require it and suggest that it makes the stems more tender to eat. Either way, peeled asparagus does not keep as long, as the peel protects the spears from drying out and locks in the flavour. If peeled asparagus needs to be stored, it is advisable to prepare it swiftly after harvesting and place it in the fridge either wrapped in a damp towel or cling film.

Storing cooked asparagus

Once cooked, asparagus does not keep well and should be eaten within 24 hours. However, to save the cooked spears for adding to a cold salad later in the day, they can be stored in an airtight container in the fridge.

Drying asparagus

If you have a real glut of asparagus, it can also be dried to store for use later in the year. To dry asparagus, blanch it first and dry in a dehydrator or slow oven. To dry in an oven, lay the spears apart on a wire rack or baking tray and place in an oven at a low temperature of 60 °C for 6 to 10 hours. Once dry it can be stored in a sealed container that can be placed in the freezer for over 6 months and be added to soups or stews as required.

How to cook asparagus

Asparagus can be cooked in many ways including steaming, boiling, baking, frying or even on the barbecue. Often cooked with little preparation other than a thorough wash, it is a delicious and versatile vegetable.

What parts of asparagus are edible?

If you are wondering how to prepare asparagus, it is wise to consider which parts of asparagus are edible. The spear stem and tip that grow above the soil are the most flavoursome parts, the base of the stem that has been underground is tough and not edible and needs to be removed prior to eating. The base of the stem can either be cut away using a sharp knife or the spear carefully bent to the point where the spear end will naturally snap off. 

After the harvesting season has finished, asparagus plants are left to mature and produce their fern-like foliage, which along with their berries, should not be eaten as they are toxic.

Recommended cooking time and methods

Asparagus can be cooked in so many different ways, with perhaps the most common methods being frying and steaming.

Once washed and with the stem ends removed, to fry your asparagus, simply place it in a preheated pan with a little oil or butter and cook, turning regularly for 5 to 10 minutes or until lightly browned. Season with salt and pepper and enjoy hot.

Asparagus is packed full of vitamins, especially B and K as well as other nutrients. Steaming asparagus can help preserve the health benefits of asparagus and only takes 5 to 10 minutes or until tender, depending on the thickness of the spears.

White asparagus has a thicker skin compared to green or purple asparagus that can be stringy and needs to be removed prior to cooking. Once peeled, it can be cooked in the same way as green asparagus but will need a longer cooking time of 10 to 15 minutes when boiled or steamed.

What to do if asparagus is bitter tasting?

Asparagus has a slightly earthy bitter flavour, which helps make it such a delicacy. However, sometimes asparagus can have a strong bitter taste that makes it unpalatable. Bitter asparagus can be caused by harvesting too much of the lower stem, climatic changes or even by overcooking. Although unappealing, the bitter taste is not toxic and can easily be remedied by removing more of the lower stalk, cooking with a little sugar or peeling. However, if prior to cooking, the asparagus appears mouldy or shrivelled it should not be eaten.