A Detailed Guide to Sowing and Propagating Sweet Alyssum

Sweet alyssum (Lobularia maritima), also known as little white flower, blooms in dense clusters during its flowering season, looking just like a sea of white. Growing sweet alyssum requires a certain amount of patience and care to make it look beautiful. Sweet alyssum grows very quickly as a creeping plant, and is often propagated by cuttings or sowing. What precautions should be taken when propagating sweet alyssum by sowing?

How to Sow Sweet Alyssum

1. Sowing time

Since sweet alyssum is fairly sensitive to heat during its growing period, and the most suitable temperature for sowing is 15°C-20°C, autumn sowing is generally carried out after mid to late September.

2. Preparation for sowing

The substrate can be nutrient soil, river sand, peat soil, etc. The substrate should be sterilized before sowing; the best method is to put it in a pot and heat it by stir-frying at high temperature to suppress the occurrence of pests and diseases.

The seeds should first be pre-germinated by soaking them in warm hot water for 12-24 hours, until the seeds absorb water and swell up.

3. Sowing steps

For the tiny seeds that are difficult to pick up with your hands or other tools, you can moisten one end of a toothpick with water, place the seeds one by one on the surface of the substrate, then cover with substrate about 1 cm thick and press down lightly.

Then place the sown flower pot into water, with the water depth at 1/2-2/3 of the pot's height, letting the water slowly soak upward. The appropriate temperature for sweet alyssum germination is 20°C; seedlings generally emerge in 5-10 days, and once they have 3-4 true leaves they can be planted out into pots.

4. Management after sowing

After autumn sowing, if a cold wave with low temperatures occurs, the flower pot can be wrapped in plastic film, which helps keep it warm and moist.

After the seedlings emerge, the film should be removed promptly, and the seedlings should be exposed to sunlight before 9:30 in the morning or after 3:30 in the afternoon each day, otherwise the seedlings will grow very weak and spindly.

After most of the seeds have sprouted, appropriate thinning is needed, and diseased and unhealthy seedlings should be pulled out, so that the remaining seedlings have a certain amount of space between each other. When most of the seedlings have grown 3 or more leaves, they can be transplanted into pots.

Sweet Alyssum Propagation Methods

Sweet alyssum can be propagated by seeds or cuttings, but seed propagation is generally more common. In northern regions it is mostly sown in spring, generally sown and raised as seedlings in a greenhouse in March. Sweet alyssum seeds germinate faster than ordinary flower seeds, with neat emergence; the suitable germination temperature is 20°C, seedlings emerge in about 5 days, and they are planted out into pots at 3-4 true leaves, flowering in June.

When the summer heat arrives, growth becomes poor and there are few flowers; at this time the spent flowering branches should be cut off, and fertilizer and water management strengthened, and it will bloom again in autumn. In North China and southern regions it is mostly sown in autumn, overwintered in a cold frame in protected ground, potted up or planted out in March of the following year, and flowers in April.

What Are the Little Care Tips for Sweet Alyssum

1. Temperature

Sweet alyssum is not very demanding about winter temperature; as long as it is not exposed to frost it can overwinter safely. It dies when the temperature rises above 30°C in late spring and early summer; the most suitable growing temperature is 15-25°C. In the three seasons of late autumn, winter and early spring, since the temperature is not very high, it should be given direct sunlight, which helps it carry out photosynthesis and form flower buds, bloom and set seed. If high-temperature weather occurs in summer, about 50% of the sunlight needs to be shaded out for it.

2. Fertilizer and water

Like other herbaceous flowers, sweet alyssum has a relatively high demand for fertilizer and water, but it is most afraid of indiscriminate fertilizing, concentrated fertilizer, and one-sided application of nitrogen, phosphorus or potassium fertilizer. It requires following the two fertilizing (watering) principles of light fertilizer applied frequently, small amounts but many times, complete nutrition, and alternating dry and wet - when dry, dry out thoroughly; do not water when not dry; when watering, water thoroughly - and after fertilizing, the leaves and flowers should be kept dry at night.

3. Pinching

Sweet alyssum is generally pinched twice before flowering to encourage more flowering branches to sprout. One to two weeks after potting up, or when the seedling is 6-10 cm tall and has six or more leaves, remove the top shoot, keeping the lower 3-4 leaves, to encourage branching. Three to five weeks after the first pinching, or when the side branches have grown to 6-8 cm long, carry out the second pinching, that is, remove the top shoots of the side branches, keeping the 4 leaves below on the side branches.

Introduction to Sweet Alyssum

1. Other names

Sweet alyssum is also called alyssum, little white flower and jade butterfly ball.

2. Origin

Native to the Mediterranean coast. In China it is cultivated for ornamental purposes in parks and flower nurseries in Hebei, Shanxi, Jiangsu, Zhejiang, Shaanxi, Xinjiang and other provinces and regions.

3. Morphological characteristics

The leaves are linear or lanceolate, tapering at both ends, with entire margins. The inflorescence is corymbose, greatly elongated in the fruiting stage; the petals are light purple or white, oblong.

Seeds number 1 per locule, suspended from the top of the ovary locule, oblong, about 1.5 mm long, light reddish-brown, with a gelatinous substance when exposed to water.

The flowering period is March to April for greenhouse cultivation, and June to July for open-field cultivation.

Cuttings are a fairly common propagation method for plants, and the survival rate is also very high, but propagating sweet alyssum by sowing is not difficult either; all of this has been described in detail above, and we hope it is helpful to everyone. If you want the sweet alyssum you grow yourself to thrive, careful tending is still indispensable.