Chitting is the process of encouraging seed potatoes to sprout before they are planted, which gives them a head start on the growing season. This pre-sprouting practice can shave up to a few weeks off the time it takes for the potato plant to emerge from the soil after planting. Gardeners utilize chitting to achieve an earlier harvest and potentially a more bountiful yield, especially for early-season varieties. The objective is to produce short, sturdy, and robust sprouts that are ready to grow vigorously once placed in the ground.
Prepping Seed Potatoes for Sprouting
Preparation begins with selecting firm, healthy seed potatoes specifically intended for planting, as grocery store potatoes are often treated with sprout inhibitors. Identifying the “rose end” is necessary, as this is the blunt end of the tuber where the majority of the “eyes,” or growing points, are concentrated. The seed potato should be positioned with this end facing upward in the chitting container, typically an egg carton or shallow tray.
Larger seed potatoes can be cut into smaller pieces to maximize the number of plants, but each piece must retain at least one or two viable eyes. These cut sections should be approximately the size of a small hen’s egg to ensure enough stored energy for initial growth. After cutting, the pieces must be “cured” by allowing them to dry in a well-ventilated, moderate environment for 24 to 48 hours. This curing process forms a protective, leathery callus over the cut surface, which helps prevent rot and fungal infection once the chitting process begins.
Setting Up the Ideal Environment
The traditional method for chitting establishes a baseline growth period of four to six weeks, requiring specific environmental controls to produce the desired sturdy sprouts. The ideal location is one that remains cool but is reliably frost-free, such as an unheated porch or garage. An optimal temperature range is between 50°F and 55°F (10°C to 13°C) to break the potato’s dormancy without encouraging excessive growth.
The seed potatoes must be exposed to indirect, bright light, which signals to the plant that the sprouts should be short and stocky. This light exposure prevents the development of long, pale, and brittle sprouts, known as “etiolated” growth, which are weak and easily damaged upon planting. The resulting healthy chits will be compact and often display a desirable dark green or purple coloration.
Accelerated Techniques for Sprout Growth
To significantly reduce the chitting time, often down to two or three weeks, gardeners can intentionally manipulate the environmental conditions to force faster metabolic activity. One method involves using a slightly elevated temperature, aiming for an initial range of 60°F to 65°F, to quickly break dormancy and initiate sprout development. Maintaining this temperature for too long risks shriveling the potato or encouraging weak growth.
Applying low, consistent bottom heat can also be highly effective for rapid chitting, which can be achieved by placing the chitting trays on a specialized heat mat. The mat gently warms the base of the potatoes, promoting quick cellular division.
Another forcing technique involves storing the potatoes in a warm, dark, and slightly humid environment. This rapidly induces the initial emergence of sprouts. Once these sprouts appear, the potatoes must be immediately moved to the standard bright, indirect light conditions to strengthen and color the chits, preventing them from becoming long, weak growth.
Assessing Readiness for Planting
Determining when the accelerated chitting process is complete is based entirely on the physical appearance of the emerging sprouts. The seed potatoes are ready for planting when the chits are short, robust, and have developed a dark green or purple pigmentation, indicating they are strong and photosynthetically active. The optimal length for these ready-to-plant sprouts is between one-half and one inch long.
For gardeners seeking to maximize the size of individual potatoes, it is advisable to remove all but the two or three strongest chits from each seed piece before planting. This practice directs the plant’s energy into developing a few large tubers rather than many small ones. The remaining stout sprouts should be handled with care to avoid snapping them off when moving the potato to its final planting location in the soil.