How to grow & care for yam
Yam (Dioscorea sp.) is an ancient food crop grown in tropical and subtropical climates as an alternative to potatoes. Just like potatoes they can be baked, mashed or fried. Yams grow best in a frost free climate with summer rains and mild dry winters and you’ll need to provide them with fence or trellis to climb up.
There are 2 main species of yam grown in Australia:
- ‘Winged Yam’ Dioscorea alata - a scrambling vine that can grow up to 1-3 metres wide and 1-5 metres tall. Normally deciduous in winter when the below ground tuber is harvested. Can be weedy in some areas.
- ‘Aerial Potato’ Dioscorea bulbifera - produces potatoes along the above ground vine, a bit like a passionfruit during late summer and into winter. Vines can grow 5-10 metres long and produce sweet smelling flowers in summer.
Yam plants need a rich fertile soil that’s been improved with plenty of compost or Scotts Osmocote Compost Premium Soil Improver before planting. If you need to grow yams in pots or planters, choose a large 50-60cm wide and deep pot or trough style planter with plenty of drainage holes. You’ll also need to position your planter near a fence or trellis for the yam vine to grow up.
Top 5 steps to growing yam
- Yam prefers to grow in a sunny position in well-drained soil. Yam vines grow big and they grow quickly! Plant yams at the base of a trellis or fence for the vine to climb up as it grows.
- Improve the soil before planting by adding plenty of compost or Scotts Osmocote Compost Premium Soil Improver
- Yam can be planted from tubers or potted plants, whichever is more readily available to you.
- Harvest yams when the leaves start falling off the vine in autumn or early winter.
- Yam’s are relatively pest and disease free.
Yam tubers or potted plants
- Scotts Osmocote Compost Premium Soil Improver
- Scotts Osmocote Plus Organics Tomato, Vegetable & Herb Plant Food & Soil Improver
- If growing in pots, Scotts Osmocote Plus Organics Premium Potting Mix and a suitable pot
- Garden trowel
Choose a full sun position to plant your yams - somewhere with a free-draining soil is perfect. Yam vines will also need a fence, support or trellis to grow up - make sure this is setup before you plant because the vines grow very quickly.
Enriched the soil before planting yam by mixing Scotts Osmocote Compost Premium Soil Improver and a Scotts Osmocote Plus Organics Tomato, Vegetable & Herb Plant Food & Soil Improver through the top 20-30cm of soil.
Planting in the garden
Plant yam tubers or potted plants 50-60cm apart into your prepared soil. If planting leafless tubers ensure they are planted around 3-5cm deep. Water in your new yam well and keep well watered throughout the growing season.
Mulch around your yam plants to suppress weeds and retain moisture.
Planting in pots
Yam can be grown in large pots 50-60cm deep by the same width. A half wine barrel with added drainage holes is the ideal size for 1 plant or look for large, rectangle planters for 2-3 plants.
Fill the pot with Scotts Osmocote Plus Organics Premium Potting Mix and plant your yam into the centre of the potting mix. Position your pot in a full sun position, up against a trellis or support.
Regular watering of yams is critical during the warmer months, it will quickly become heat stressed and produce less tubers if left to dry out. Mulch the top of your potting mix around the yam plant to suppress weeds and retain moisture.
You’ll notice the leaves of the yam plant begin to yellow and die back as harvest time arrives in autumn. Above-ground yams can be picked off the plant easily. Below-ground growing yams should be carefully dug up to avoid damaging the tuber.
Tubers will store well in a cool, dry place for many months.
Pests & Diseases
Yams are relatively pest and disease free.