How to Grow Shallots
Grow Guide #2317
Binomial name: Allium cepa var. aggregatum
Life Cycle: perennial (usually grown as an annual)
This 'How to Grow' guide details everything a home gardener needs to know to plant, grow and care for Shallots (Allium cepa var. aggregatum).
When to Plant Shallots
Shallot is a cool season crop. Use the table below to identify the best time of year to sow shallot in your climate.
Shallot plants are best grown in full sun. Choose a location that will receive at least 6 hours of full sun each day.
Shallot plants need a loose, well drained soil enriched with organic matter. Prepare soil by weeding it thoroughly, digging it over to at least a spade’s depth to loosen the soil, and adding aged animal manure or compost. Organic matter can be dug into heavy soil to lighten it so roots can grow freely. Keep the area free of weeds until planting. Learn more about preparing soil for planting here.
How to Plant Shallot Bulbs
Shallot bulbs are best planted directly in the garden.
- Plant individual bulbs 20cm apart with the pointed tip facing upwards and just visible above the surface of the soil.
- Cover with soil and water in well.
- Keep soil moist but not wet until shoots emerge.
How to Grow Shallots
Shallot plants may need watering during the growing season. Water when the soil is dry about 5cm below the surface (test this by scratching away a little soil with your finger). Water deeply in the early morning or late afternoon. Avoid watering the leaves of plants to avoid fungal diseases. Learn more about watering here.
If soil was well prepared no extra fertiliser should be necessary. Fertilising can result in excessive leaf growth at the expense of roots forming. In poor soil use a fertiliser low in nitrogen and high in phosphorus, such as blood and bone, applied at the recommended rate.
How to Harvest Shallots
Shallots should be ready to harvest in approximately 120 days.
Shallots are ready to harvest when the leaves begin to fall over and before the plant flowers. Use a fork to gently lift the entire plant from the bed, shaking off the excess soil. It is a good idea to harvest a single plant first to make sure a bulb has formed; if the bulb is small or unformed, leave the remaining plants for 2-3 weeks then harvest and check another bulb.
Place the whole plants on wire racks or hang them in bunches, leaving them in a dry cool place for 2-3 weeks to cure. Cut the dried leaves off 3-4cm above the bulb. Shallot bulbs can be stored in a cool dry place for up to 6 months.
Common Problems when Growing Shallots
Like all plants, shallot is susceptible to some pests, diseases and other problems. Below is a list of the most common problems gardeners encounter when growing shallot plants:
- Aphids are small (2-4mm long) sap-sucking insects that congregate on the new shoots or the undersides of leaves. They can cause leaves to wilt or become discoloured, and also excrete honeydew which can attract ants and other insect pests. To manage aphids, remove them by spraying with a garden hose, apply a soap or alcohol spray, or encourage predatory insects to your garden. Read more about aphids here.
- Bulbs not forming can be caused by harvesting too early, inconsistent watering or weather, planting bulbs or cloves that are too small, or too much nitrogen during the growing season. Plant varieties suited to your climate, do not over fertilise, water regularly and harvest after the leaves have started to die down.
- Bolting is when a plant prematurely flowers and goes to seed. Bolting can be caused by a period of extreme weather. Avoid sowing seed until after the danger of frosts has passed or in very hot weather. Water plants regularly and deeply in hot weather to prevent them suffering heat stress.
- Rust (Puccinia sp.) is a fungal disease that causes brown to orange raised spots or patches to appear on foliage. Fungal spores are spread by wind or water to neighbouring plants, especially in temperatures of 10-20C and when humidity is high. To manage rust, space plants to avoid overcrowding, grow them in the recommended amount of light (eg full sun), do not over fertilise crops, remove dead plants and practice crop rotation. Read more about rust fungus here.
- Onion thrips (Thrips tabaci) are flying insects less than 1.5mm long with slender pale yellow to light brown bodies. They suck sap from plants, leaving silver patches on the leaves and reducing the productivity and yield of plants. Thrips can live in the inner leaves and leaf folds of alliums, and may also infest bulbs. Wash thrips from affected plants using a garden hose, spread an organic mulch around plants, and encourage predatory mites and lacewings with companion planting.
- Rotten bulbs are caused by pathogens entering bulbs after sitting in cold, wet soil, being temporarily waterlogged or being exposed to warm temperatures in winter. Bulbs may show obvious signs of rot, have no roots or shoots, or produce stunted yellow leaves but no flowers. Plant bulbs in free-draining soil, raised garden beds or containers; do not water bulbs over winter; and lift and store bulbs over winter if recommended for your climate.