When to Plant Potatoes
The first step is to determine the recommended planting time for your climate. Since it takes potatoes two to three weeks to emerge from the ground, the earliest you should plant seed potatoes is two weeks before your last anticipated freeze date of -2 degrees to 0 degrees C, or 28-29 degrees to 32 degrees F . (If you don't know your local last freeze date, you can find it here .) About a week before your planting date, bring the seed potatoes out of the fridge and place them in a bright, warm window for about a week. This will help break the spuds' dormancy and assure they will grow quickly when you put them into the still-cool spring soil.
Q: Does planting potatoes in a deep mulch on uncultivated ground still give reasonably good yields?
A: This deep mulch potato planting technique was passed on to the Perth Dupont Community Garden in the spring of 2008, from another community gardener. She called it the "No Work Potatoes" from popular organic gardener Ruth Stout .
We took one bale of straw, and spread it out over a 1m X 1.5m area, over the potatoes, so that the straw was fluffed out -about .5m high. It was wonderful! The potatoes got a good chance to expand, because there was no soil compressing them.
As well, the straw acted as insulation, keeping the potatoes at an even temperature...18-20C (21C is room temperature). They never got hot. The added bonus was how soft the soil became; you could swish your hand in it, almost like water!
We found that, at least in our limited experience, this method did not compromise the yield.
LAST FROST DATE: Check the OldFarmer's Almanac
From the last frost date, work back two weeks to determine the planting date, and then go back an extra week, to figure out when to get your potatoes out of the fridge to break their dormancy.
The last frost date for Toronto 2009 is May 9th.
So the guideline for Toronto gardeners for 2009 is: Take the potatoes out of storage during the second week of April (11th), and plant them during the third week of April (18th).