Asparagus is quite an easy plant to grow, but you have to be patient to harvest your first tender spears. The plant goes dormant over winter and produces fresh new growth in spring.
It takes around 3 years of growth to start harvesting asparagus spears if you grow from seed. However, asparagus can also be grown from dormant crowns. If the crown is 1 year old, it will take 2 years before you can start harvesting the spears.
Here’s everything that you need to know about the growth cycle of asparagus plants.
How Long Does It Take To Grow Asparagus From Seed?
Growing asparagus from seed means that you have to be patient. This is because it will take 3 years from planting before you can successfully start to harvest the edible spears.
However, if you have a large family and everyone loves asparagus, then this is one of the most economical ways to grow this perennial. You can also get quite a large variety of asparagus seeds, whereas the crowns are usually only available in a few select varieties.
It’s best to start your seeds indoors so that the little plants will be ready to go into the ground as soon as the danger of frost is over. The seeds will take a little time to germinate, so you just have to be patient.
Use a premium-grade potting mix to plant your seeds, and then add some seed-raising mix to the top. Then you can sprinkle the seeds over the mix and cover with a thin layer of seed-raising mix. Make sure you firm down the soil to ensure that it has good contact with the seeds, as this will help to speed up germination.
Keep your pots in a sheltered spot and ensure that you keep the soil nice and moist. Then just sit back and wait for the tiny seedlings to start emerging. Because the seeds are quite small, you’ll most likely get quite a number of plants per pot.
How Long Does It Take Asparagus Seeds To Germinate?
Asparagus seeds can take around 21 days to germinate, but sometimes, this can be even longer. You also might find that the seeds will germinate at different times. But don’t worry about this, as it will take the seedlings several weeks to grow tall enough to be ready for transplanting.
You can make sure that your seeds germinate well by keeping the soil warm. If starting indoors, provide some bottom heat with the use of a heating pad under the trays or pots. Asparagus seeds prefer the soil to be around 70 degrees Fahrenheit (21 degrees Celsius) to germinate well.
Should I Plant Asparagus Seeds Indoors Or Outdoors?
It’s best to start your asparagus seeds indoors around 12 to 14 weeks before the last frost is due. This is because asparagus seeds are slow to germinate, and the emerging seedlings can take a number of weeks before they reach a height of 2 inches and are then ready to transplant into the garden.
Once the young seedlings are ready to transplant, divide them up into individual plants and follow the planting guide below for crowns. Remember when choosing a suitable site for your asparagus that these plants will remain in the same position for many years.
It’s also possible to grow asparagus in pots. If you have a large pot, you can even put two plants into it.
Asparagus Life Cycle
The asparagus life cycle is quite an interesting one as it differs greatly from many other types of vegetables that we grow as backyard gardeners. Asparagus is a perennial, and some plants can live and produce edible spears for 15 years or more.
Here’s how an asparagus plant grows and develops:
- The seeds germinate, and the young seedlings start to develop a crown beneath the soil.
- In their first spring, the crown will send up shoots or spears, but these should be allowed to develop into ferns. It’s important not to cut any spears in the first two years of growth because the plant needs to put all its energy into producing good strong roots. This will help to give you far better yields in years to come.
- During the warm weather, the young spears will develop into their fern-like growth and become quite tall. During this time, the young spears can grow around 7 inches per day.
- As the weather cools down, the ferns will become dry and brown. When this happens, you can safely cut them down at ground level. This will encourage the plants to go dormant.
- In their 3rd spring, asparagus plants will produce new spears right throughout their growing season. Now you can harvest these spears once they reach a suitable height and are about the thickness of a pencil. It’s important to leave some of the spears that pop up toward the end of the season to develop into ferns, as these will help to store food in the crown for the following year’s production.
It’s interesting to note that a mature asparagus plant that has been maintained correctly and not harvested too soon can produce around half a pound of asparagus spears over an eight-week period.
How Long Does It Take To Grow Asparagus From Crowns?
Most asparagus plants are available as one-year-old crowns. Nurseries and garden centers normally have these available during the colder months when the plants are dormant. You can also find these available from mail-order companies during the fall. These one-year-old crowns take around two years of growth before you can safely harvest the spears for consumption.
However, if you have the patience and leave the harvesting until the second year, each plant should produce edible spears for 15 to 30 years. The reason that you shouldn’t harvest the spears in the first year of planting the crowns is that the plant needs to put all of its energy into producing a good strong root system and healthy crowns.
When planting your crowns, you should create a trench that is around six to eight inches (15 to 20 cm) deep and twice as wide. Create a 2-inch high mound in the center of your trench. Position the roots above and around this mound. Then cover the plants with around 2 inches of soil.
Once the spears start to grow and are around two inches tall, add more soil to cover the plants but leave the tips of the spears exposed. Continue to add more soil as the spears grow until the top of the soil is at ground level. Then, mound the soil slightly around the plants to avoid water-logging.
In some instances, you can find two-year-old crowns for sale in the cooler months, although these will be a little more expensive. If you happen to score a few of these, then you can start harvesting the spears the following year. Remember that harvesting your spears too soon will reduce your yields from each plant and can also result in inferior-quality spears.