Vegetable · Apiaceae
Parsnip
Pastinaca sativa
Sow it, wait with a little faith, and let a hard frost finish the job, and the parsnip turns sweet and nutty below the soil.
Full sun
Every 5–7 days
36–75°F · 2–24°C
100–130 days
Overview
The parsnip is a friendly cool-season root crop in the carrot family, grown for the pale, tapering taproot it quietly builds underground over a long season. It is a biennial, though most gardeners treat it as an annual and lift the root in its first autumn instead of waiting for it to flower. Sweet, starchy, and gently nutty, it has warmed northern kitchens for centuries, and it is far more forgiving than its slow start suggests.
The main thing this crop asks of you is patience, and that is something anyone can give. The seed is slow and short-lived, the plant takes its time, and the roots want 100 to 130 days before they are worth pulling. In return you get a vegetable that actually gets better with cold, since a hard frost turns its starch to sugar and deepens the flavor, so time is on your side.
Growing a good parsnip really comes down to the soil and the wait, and both are within easy reach. Give it deep, loose, stone-free ground to run straight down through, keep the bed moist while the slow seed wakes, and hold off harvesting until the frosts arrive. One kind reminder travels with the crop: the leaves and sap can burn skin in sunlight, so handle the tops with a little care and you will be just fine.
Care
The short version: give parsnips full sun and deep, loose, stone-free soil, about an inch of water a week to keep growth steady, only light feeding, and a long, easy wait through to a frost-sweetened autumn harvest.
Light
Parsnips love full sun for the fullest roots, though they will happily put up with partial shade. Less light just means a smaller harvest, so hand them the brightest spot you have and they will reward you.
Water
Keep the soil evenly moist, around an inch of water a week, and the roots stay smooth. Swinging between bone dry and soaked is what makes them split or crack, and steady moisture matters most during the long stretch before the seed comes up, when a dried, crusted surface can quietly stall germination.
Soil
This is the one that really counts, and getting it right is easy once you know. Parsnips need deep, loose, well-drained sandy loam cleared of stones and clods to a depth of 12 to 18 inches, or the taproot forks instead of running straight. Aim for a pH of 6.0 to 7.0 and you are set.
Temperature
These are tough, easygoing plants that grow across a wide band, roughly 36°F to 75°F (2°C to 24°C). The roots take frost in the ground without complaint, and that cold is the very thing that sweetens them.
Humidity
Plain outdoor air suits them just fine, somewhere around 40% to 70%, and there is nothing to fuss over here. The moisture in the soil is what truly matters.
Feeding
A light touch is all they ask. Feed once at sowing and again mid-season with a balanced, low-nitrogen fertilizer, because too much nitrogen or any fresh manure nudges the roots into forking and going hairy instead of clean.
Pruning
Happily, parsnips need almost no pruning. Thin the seedlings to 3 to 4 inches apart once the true leaves appear so the roots have room to swell, and snip off any flower stalk that tries to bolt in the first year.
Size & spacing
The leafy tops stand about 12 to 18 inches (30 to 45 cm) tall and spread 8 to 12 inches (20 to 30 cm). Thin the plants to 3 to 4 inches apart in the row so every root has the space it needs to fill out.
When to plant
Parsnips keep an unhurried clock, and that is nothing to fret over. Direct sow in early spring, a few weeks before the last frost, once the soil is workable and at least 40°F (4°C), then simply let them size up all season. Hold the harvest until late fall and through winter, because a hard frost is exactly what makes the roots sweet.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Plant: Direct sow in early spring, 2-4 weeks before the last frost, once soil is workable and at least 4°C (40°F); parsnips do not transplant well due to the taproot.
- Harvest: Harvest roots in late fall and through winter; flavor sweetens markedly after one or more hard frosts converts starch to sugar.
Hardiness
USDA hardiness zones: 2–9
Temperature: down to -46°C
Troubleshooting
Most parsnip troubles happen quietly, either at sowing or down in the root, and nearly all of them are recoverable. A bare row or an odd-shaped root usually traces back to the seed, the soil, or the weather. Find the closest match below, sort out the cause, and next season will go more smoothly.
Waiting weeks and still seeing a bare row
Take heart, because a no-show row almost always comes down to one fixable thing: parsnip seed does not keep well, so seed saved from a past year is the usual culprit. The seed also wants 14 to 28 days and a bed that stays damp the whole time, since a dry, crusted surface will hold it back. Start with a fresh packet each spring, keep the surface gently moist until you spot green, and scatter a few quick radishes so you always know where the row sits.
Fix:
- Sow fresh seed each season
- Keep the seedbed continuously moist until emergence
- Cover the row lightly to prevent crusting and interplant fast radishes to mark the row
Roots that split, fork, or come up whiskery
This one looks worse than it is, and it is easy to prevent next time. A parsnip needs a clear path straight down, so stones, clods, and heavy ground are what nudge the taproot into forking and branching. Fresh manure or a heavy hand with nitrogen brings on the same hairy roots, and so does moving a young plant. Loosen the bed deeply and lift out the rocks before you sow, keep any feeding low in nitrogen, and always sow right where the crop will grow.
Fix:
- Cultivate and de-stone soil deeply before sowing
- Use low-nitrogen, well-rotted amendments only
- Direct sow rather than transplant
Dark, sunken patches where the shoulders meet the soil
Do not be discouraged if you spot this, since it is a known problem with a clear answer. What you are seeing is canker, a fungal rot that settles into wet, poorly drained ground and slips in through cracks or nicks at the crown. A soggy season makes it more likely. Help the bed drain better, mound a little soil over the exposed shoulders, and lean on forgiving types like Gladiator or Cobham Improved Marrow that shrug canker off.
Fix:
- Improve drainage
- Hill soil over exposed shoulders
- Grow canker-tolerant cultivars such as 'Gladiator' or 'Cobham Improved Marrow'
Rusty little tunnels winding through the roots
Those rust-brown trails are nothing you caused, so there is no need to feel bad. They are the feeding tracks of carrot rust fly larvae, which mine the lower root while the adults visit the leaves in spring and late summer. Lay a floating row cover over the bed to keep the flies away, shift the planting off last year's carrots and parsnips, and wait out the early flight before you sow.
Fix:
- Cover rows with floating row cover
- Rotate away from previous carrot/parsnip beds
- Delay sowing to avoid peak fly flights
Toxicity
The parsnip you eat is a safe, wholesome root once it is peeled and cooked, and a stray nibble will not harm a pet, so there is no need to worry there. The one hazard lives in the foliage and sap, which carry furanocoumarins that can burn skin in sunlight, so handle the tops with gloves and keep animals from grazing the leaves freely.
Toxic to
Cats · Dogs · Horses · Rabbits · Livestock · Birds
Safe for
People
Cats Mild
You can relax about the root, since the ASPCA does not list parsnip as toxic to cats and a curious nibble is no cause for worry. The part to watch is the sap on the leaves, which can leave the mouth or thin-furred skin a little sore, so it helps to keep a cat away from the tops.
Dogs Mild
Rest easy here too, because parsnip is not on the ASPCA toxic list for dogs and the cooked root is harmless. A dog that gnaws the leaves might get some mouth irritation from the sap, and sap on bare skin can sting in sunlight, so the safe move is keeping the foliage out of reach.
Horses Mild
Horses graze parsnip tops with little trouble, so there is no need for alarm. The furanocoumarins in the leaves can leave pale, thin-skinned spots like the muzzle sore once the sun hits, so a quick look for any redness or peeling after time in the patch keeps everyone comfortable.
Rabbits Mild
A little parsnip makes a happy treat for a rabbit, and the root does no harm at all. Just go gentle with the leafy tops, since the sap can irritate, and offer only small amounts at a time.
Livestock Mild
Cattle, goats, and sheep can eat parsnip foliage without much fuss. The same sun-triggered compounds may redden or blister pale, exposed skin around the face, so simply keep heavy grazing of the green tops in check.
Birds Mild
Backyard hens peck at parsnip root and kitchen scraps with no bother at all. The leaves carry the irritant sap, so it is kindest not to heap fresh tops into the run.
People Root safe, sap a hazard
The peeled, cooked root is a sweet, wholesome vegetable that is perfectly safe to eat. The one real hazard is the sap on the leaves and stems, which holds furanocoumarins that trigger phytophotodermatitis, a painful sunlight-driven rash with blisters and brown marks that linger. Wear gloves and long sleeves when cutting or weeding the tops, and wash any sap off your skin before heading into the sun.
Wear gloves and long sleeves when cutting, weeding, or handling parsnip tops and sap, especially in sun; wash skin promptly if sap contacts it and keep that skin out of sunlight. The root is safe to eat once peeled and cooked.
Helpline numbers
United States
ASPCA Animal Poison Control: (888) 426-4435 (fee applies)
United Kingdom
Animal PoisonLine: 01202 509000 (fee applies)
Australia
Animal Poisons Helpline: 1300 869 738
Varieties
Parsnip varieties mostly differ in root shape, sweetness, and how well they stand up to canker, and any of these makes a friendly place to start. These are the ones you are most likely to come across.
Hollow Crown
A long-rooted heirloom with broad shoulders and a sunken crown that gives its best only where the soil runs deep and stone-free enough for it to drive straight down.
Harris Model
A well-loved home-garden choice, valued for smooth, even white roots with a fine texture and a dependable sweetness.
Gladiator F1
A strong hybrid that stands up to canker far better than most and still delivers smooth, uniform white roots you can count on.
Cobham Improved Marrow
A sweet, canker-tolerant variety with clean-skinned, medium-length roots that settle in happily across many gardens.
Companions
Parsnips do best near plants that mark their slow rows or keep the soil open, and worst beside relatives that share their pests.
Plant near
Radish: Fast-germinating radishes mark the slow parsnip rows and loosen the soil.
Bush beans: Legumes fix nitrogen and do not compete for the deep root zone.
Onion: Pungent alliums can help mask the crop from root-fly pests.
Keep apart
Carrot: Shares pests and diseases such as carrot rust fly, increasing pressure when grown together.
How to propagate
There is just one way to begin a parsnip, and it could not be simpler: sow the seed right where it is going to grow.
SeedModerate
Direct sow in early spring into workable soil · Germination takes 14-28 days; roots reach harvest size in about 100-130 days
There is only one way to raise a parsnip, and it is simple: sow the seed straight into its final spot, since the taproot will not forgive being moved. Reach for a fresh packet every year, because the seed fades quickly, and sow in early spring as soon as the soil is workable. Then comes the gentle part, patience, as the seed can take 14 to 28 days to wake up, so keep the bed evenly moist the whole while, and the roots will be ready to lift about 100 to 130 days on.
Myths
Parsnips are just white carrots.
They may look like cousins, but parsnip and carrot are different species, Pastinaca sativa and Daucus carota. Parsnip comes out sweeter and starchier, and its flavor grows richer once a frost has passed.
Parsnip leaves are safe to handle like any other garden green.
The leaves and sap carry furanocoumarins, and once they touch skin and meet sunlight they can bring on phytophotodermatitis, a blistering chemical burn. So handle the tops with gloves and covered arms, and keep any sap off bare skin to stay comfortable.
Parsnips are inedible until they have been through a frost.
Good news: you can eat them any time, frost or not. Cold simply converts some of the starch into sugar, so a frosted root just tastes sweeter rather than only then being fit to eat.