The daffodil is a common name for the genus Narcissus of which there are fifty or so species and a fantastic 130,000 varieties when including cultivars and hybrids. In some areas of the country, all yellow daffodils are mistakenly called by the common name jonquil, which is the species name of N. jonquilla. Jonquil bulbs need to be planted in the fall when soil temperatures have started to cool right before the first frost. Select firm, healthy, large bulbs. Planting depth will depend on the bulb, but a good rule of thumb is to dig a hole about 3 times the depth of the bulb size. Place the jonquil with the pointy end facing upward, leaving at least 4 inches between each bulb. After three to five growing seasons, dig up and divide the bulbs and spread them around the garden.
Light
Jonquils will perform best if planted in full sun, but they can tolerate some light shade and still produce. For the most blooms and the best spring show, place the plant in a sunny location, and it will not disappoint.
Soil
Daffodils grow in many soil types. However, well-drained soil that is rich in organic matter will yield the best results. Good drainage is imperative to keep bulbs from rotting. Less fertile soil is better than overly highly rich soil that will produce excess foliage and fewer flowers. Slightly acidic soil is best, so you might add soil sulfur if you have alkaline soil.
Water
All Narcissus need a good amount of water while during their growing period. Jonquils should be watered immediately after the bulbs have been planted. Watering should continue three weeks after the flower blooms to ensure good production for next year.
Foliage
Do not cut the foliage of jonquils after blooming. The foliage absorbs energy and stores it in the bulb to produce blooms the following year. Wait until the foliage has turned brown and died back before you trim the leaves.
Temperature and Humidity
It is important to remember that all Narcissus bulbs require a cooling period to bloom in the spring during their dormant winter. Jonquils need to be planted when the soil temperature is consistently 40 to 45 degrees Fahrenheit to accommodate this cooldown period. Jonquils are hardy from USDA Zones 4 to 8 to negative 15 degrees Fahrenheit.
Fertilizer
The best time to fertilize your jonquils is during planting and soil prep. Mix in a low-nitrogen fertilizer into the soil. A 5-10-10 is a good fertilizer for this purpose. Yearly applications of bulb fertilizers can be added to the bed before emergence. The key to the formulation is low nitrogen and high phosphorous.
Jonquil vs. Daffodil
What makes a daffodil a daffodil and what makes a jonquil a jonquil is the first thing that should be cleared up. The short answer is: All jonquils are daffodils, but not all daffodils are jonquils. There are 13 divisions of Narcissus, based on flower shape and other characteristics. Jonquilla is one of the 13 divisions. Like most things in life, it is not that easy, though. It is not very clear when you see a mass of Narcissus growing together. First, yes, jonquils are yellow. However, there are also yellow daffodils; the flower of the jonquil differs by number. There are usually four or five jonquil flowers per stem, and these are fragrant compared to other Narcissus. The dead giveaway that distinguishes the species will be the leaves of the jonquil. The leaves compared to daffodils are much different: jonquil leaves are similar to reed grass and will be round and hollow. “Guidelines for Growing Daffodils.” Daffodilusa.Org, https://daffodilusa.org/growing-daffodils/guidelines-for-growing-daffodils/.
