Potato Growing Guide

Few things are as satisfying as growing your own vegetables and potatoes are one of the most fun crops with the prospect of having new potatoes on the table for a traditional Christmas dinner always a motivating factor.

Potatoes are a very easy crop to grow with varieties suitable for early planting (for those Christmas dinners) through to main crop varieties which take longer to mature but can be stored for later use.

Planting

What

Potatoes are susceptible to several viruses that can reduce yield so plant only certified seed potatoes available from RD1 in 1 and 3kg bags. 25kg bags are also available on request. RD1 only sell high quality South Island grown Morton Smith-Dawe certified seed potatoes.

When

Plant when frosts have passed in early spring through to early summer and make sure any new shoots are covered with frost cloth should a late frost be likely as potatoes are extremely frost sensitive.

Where

Plant potatoes in a warm, sunny, sheltered well drained location avoiding the same location as tomatoes or potatoes from the previous season. Early maturing varieties require less space than main crops which require lots of space. Compost can be added if required but dig in some Tui Potato Food one week prior to planting at the rate of 300g per square metre. Blood and bone can also be used but don't be tempted to be overly generous with fertiliser at planting as potatoes prefer to be fed regularly throughout the growing season. Don't add lime. Potatoes can also be grown inside a stack of old tires or planted in pots or containers by continually adding more soil as the plant grows upwards.

Growing

How

Early crop varieties should be pre-sprouted before planting by placing a single layer of potatoes on a tray (egg trays are perfect) in warm well lit location until small spouts appear. When the shoots are 10 to 20mm long remove all but sturdiest shoot and the potatoes are ready to plant. Allow 4 to 6 weeks for the sprouting process which helps the potatoes to establish better when the soil is still cool. Main crop potatoes can also be sprouted but this is not necessary once the soil has warmed. Impatient gardeners have been known not to bother with the sprouting process at all.

Plant potatoes in trenches about 75mm deep with the shoots pointing upward , 250mm apart for early crops and 300mm for main crops with furrows 850mm to 1m apart and cover with soil taking care not to damage the shoots. Once new growth appears above the surface mound the soil around them to protect new growth and prevent the tubers becoming exposed to the light which causes them to turn green. Mound the potatoes regularly until flowering when growth will slow down. Don't underestimate the importance of mounding your potatoes as the crop forms on the stem of the shoots.

Care

Feeding

Potatoes are "gross feeders" so fertilise regularly during the season with Tui Potato Food and water regularly during dry spells aiming to keep the soil moist by watering between the mounds rather than onto the leaves which can cause blight.

Harvesting and storage

Early varieties can be harvested for immediate use once plants are flowering fully. Don't dig main crops until the foliage had died down and become quite dry usually during March. Carefully dig the tubers using a digging fork taking care not to damage the skin. If planning to store the potatoes (best keepers are Karaka , Desiree , Rua , Red Rascal , Ilam Hardy and Agria .) remove any damaged ones as these will rot and potentially spoil the whole bag. Store potatoes in heavy paper bags or thick hessian sacks in a cool, dark well ventilated place making sure rodents do not have access and check occasionally removing any rotten ones. Potatoes should keep for up to 6 months if stored carefully.

Attention

Many problems can be avoided by ensuring potatoes are not planted in the same place each year or where tomatoes have been planted previously. Blight is the most common disease and this is best treated with preventative sprays like Copper Oxychloride. Watch for insect invasions like aphids and regular mounding will help prevent the Potato Tuber Moth and other insect attacks.

Potato variety listings^

First crop early planting

• Cliff Kidney Waxy potato good for boiling, salads, casseroles and soups. Great flavour.
• Jersey Benne Waxy potato good for boiling, salads, casseroles, soups and mashing.
• Liseta Firm cooking waxy potato ideal for boiling, salads, casseroles, soups and roasting. High yielder.
• Maris Anchor Excellent as an early boiling potato and suitable for roasting. Great flavour.
• Rocket Great boiling and roasting potato.
• Swift Waxy potato ideal for boiling, salads, casseroles and soups. High yielder.

Second crop early/main planting

• Allura Very versatile and suits all cooking requirements. Holds firm on cooking. Very high yielder.
• Heather Waxy potato ideal for boiling, salads, casseroles, mashing and roasting. Excellent flavour.
• Ilam Hardy Floury potato ideal for mashing, baking, roasting, chips and wedges. Good keeper.
• Karaka Great all round cooking potato, excellent flavour. High yielder. Good keeper.
• Nadine Waxy potato good for boiling, salads, casseroles and soups.
• Purple Heart Great for salads, boiling and microwaving. Strong in antioxidant.
• Purple Passion Excellent cooking qualities great for boiling and chips. Holds firm on cooking.

Main crop

• Agria Floury potato, good all purpose cooking. Great for chips. High yielder. Good keeper.
• Desiree Good for all general cooking, great to microwave. Good keeper.
• Red Rascal Floury potato, good all purpose cooking. Suit organic growing. Good keeper.
• Rua Good for roasting or boiling. Good keeper.
• Karuparera Waxy potato, ideal for boiling, baking and chips (Maori Potato). Good keeper. Demands watering.
• Huakaroro Waxy potato, ideal for boiling, has a buttery taste (Maori Potato). Good keeper. Demands watering.
• Tutaekuri (Urenika) Ideal for boiling and baking (Maori Potato). Good keeper. Demands watering.

^Not all varieties are stocked in all stores