How to Grow Root Parsley Seeds
Grow Guide #2341
Binomial name: Petroselinum tuberosum
Life Cycle: Biennial (usually grown as an annual)
This 'How to Grow' guide details everything a home gardener needs to know to plant, grow and care for Root Parsley (Petroselinum tuberosum).
When to Sow Root Parsley Seeds
Root Parsley can be grown year-round in most climates. Avoid planting in extremely hot or cold weather which can affect germination and growth. Use the table below to identify the best time of year to sow root parsley in your climate.
Root Parsley plants are best grown in full sun or part shade. Choose a location that will receive at least 3 hours of full sun each day.
Root Parsley 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 Sow Root Parsley Seeds
Root Parsley seeds do not require any treatment (eg soaking, stratification) before sowing.
Root Parsley seeds grow best when they are sown directly into the garden.
- Sow seeds directly in the garden 5mm deep and 30-40cm apart, with rows 30cm apart.
- Keep soil moist but never wet or dry.
- Seeds should germinate in around 14-28 days at a soil temperature of 10-30°C.
- Young seedlings will need protection from pests, pets and weather until they are established.
Root Parsley is a cool season crop that will bolt in very hot weather. Do not transplant seedlings or sow seeds outside in very warm temperatures.
How to Grow Root Parsley
Root Parsley 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.
Optional: To give plants room to grow, thin seedlings when they are large enough to handle. Pull out any weak or small seedlings so plants are spaced about 30-40cm apart.
Tip: To prolong the life of the plant, remove flower stalks as soon as they appear.
How to Harvest Root Parsley
Root Parsley should be ready to harvest in approximately 100-130 days.
Leaves are ready to harvest when they are large enough to eat, and can be harvested as needed. Harvest leaves by pinching off the outer leaves, leaving some on the plant for future growth. Eat leaves as soon as possible after harvesting. Store leaves short term in a perforated plastic bag in the fridge. For longer term storage, leaves can be frozen whole or chopped and frozen in ice cube trays.
Roots are ready to harvest when they are large enough to eat, and can be harvested as needed. Harvest individual roots by gently pulling at the base of the leaves, or use a garden fork to lift multiple roots from the soil. Shake off any excess soil and cut the foliage 1-2cm above the top of the root. Store roots short term in a perforated plastic bag in the fridge.
Common Problems when Growing Root Parsley
Like all plants, root parsley is susceptible to some pests, diseases and other problems. Below is a list of the most common problems gardeners encounter when growing root parsley plants:
- 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.
- Carrot fly (Psila rosa) is a flying insect that lays its eggs in seedlings. When the larvae hatch they live in the soil and burrow into the roots to feed. Include companion plants in your garden or use insect exclusion netting over your crops to deter the pests.
- Forked roots are usually caused by stony or heavy soil such as clay. The roots cannot grow freely in the soil or hit rocks or other obstacles and split into two. Cultivate the soil well before planting, dig in some coarse sand or compost to lighten the soil, or grow round or short varieties suited to heavy soil.
- Small roots can be the result of sowing too thickly or over fertilising. Thin seedlings to give roots adequate space to grow. Do not fertilise plants as this may encourage the growth of foliage at the expense of roots.
- Split roots are usually caused by inconsistent watering when roots are mature. Water deeply and evenly to keep soil moisture consistent and always take recent or expected rainfall into consideration before watering.
- Tough roots usually indicate that the roots were harvested too late. Harvest roots when they are young and tender.
- Whitefly is a sap-sucking insect related to aphids. They are often found in large numbers on the underside of leaves and will swarm in clouds when disturbed. Plants may have yellowing leaves or may wilt, and growth will be slowed. Whitefly can be removed with a garden hose or sprayed with soap spray. Badly affected plants should be destroyed. Attracting beneficial insects that will prey on whitefly can be beneficial. Read more about managing whitefly here.