Chitting is the controlled production of sprouts on seed potatoes before planting. But the controlled production of sprouts is the key. The length & strength of the sprout must be controlled to give a short (1.5-2.5cm (0.5-1in) long), stubby, green chit.
The 3 factors involved in chitting are:
- temperature – 4 degrees Celsius is ideal, but the temperature should not go above 10 degrees, neither should it reach freezing.
- ventilation – plenty of fresh air
- light – plenty of light – but not bright sunlight – a north facing window is best
Early and late main crop potatoes could especially benefit from the chitting , but it must be done properly.
When potatoes open their eyes and start to grow the small shoots produced are called chits. Sometimes gardeners encourage the growth of these chits by a process known as chitting, because planting a chitted potato reduces the time between planting and harvest.
- Chits are the sprouting shoots that grow out of the eyes of a potato.
- The small stems are called chits.
- They are kept cool so they grow slowly
- This makes them plump and strong
- The light makes them green
short, plump, strong chits will help the potato get off to a quick start when they are planted in the ground.
This will mean new potatoes will be dug a few weeks early!
It is not necessary to chit potato seed, but it is advantageous.
Chitting does bring an earlier crop because chitting starts the growing process.
- This is particularly important for new or early potatoes, as the growing season is short & every day counts!
- Many people do not chit maincrop potatoes because the potatoes seem to catch up over the long season.
Chitting does act as an insurance. If the planting season is delayed because of bad weather, or family duties, the potatoes have actually started growing so will not be quite so delayed.
Chitting is not necessary, but it does start the shoots growing on the seed potatoes, so chitting is popular with early potato growers.
When is Potato Seed Ready to Plant?
Potato seed is always ready to plant – but it should not be planted until the weather and soil conditions are favourable.
Potato seed is often chitted, so that it has started to grow before it is put in the ground.
The ideal potato chits are dark green and stubby, and will be ready to plant when the ground & weather conditions are suitable.
In an ideal world the potato seed will be hardened off, by placing it outside during the day, to get it acclimatised, before planting. But it is often not possible to do this.
Chitting potato seed gives the seed a good start and means that the new potatoes will be ready to harvest earlier. But the condition of the chit does not dictate when the potato seed is ready to plant. It is the soil & weather conditions in the garden which say when the seed is ready to plant.
How Many Sprouts or Chits on each Potato?
Most potatoes naturally produce one main chit (sprout). This is apical dominance.
The eye at the rose end of the potato (ie furthest from where the potato was attached to its parent plant) is dominant. This dominant eye is at the ‘apical’ end of the tuber, & it supresses the sprouting of other eyes.
Is it better to plant a potato with one main chit, or lots of chits?
- One main chit will produce fewer larger tubers.For early potatoes, this will bring an earlier harvest.
- Knocking off the main chit, desprouting, may result in more stems and smaller tubers, because apical dominance is eliminated.
- Cutting tubers into pieces breaks apical dominance between eyes, releasing eyes to sprout.
Other factors will effect sprouting:
- Seed planted in light, sandy soil which warms rapidly tend to produce more stems and set more tubers & result in smaller harvested tubers.
- Later planting tends to produce more stems per plant and have a lower yield.
- Sprouting of tubers under light produces short, tough green sprouts.
- enhances emergence
- tuber formation
- vine size
- earlier maturation – as much as 2 weeks.
Chit for early harvested yield.
When planting chitted tubers:
- avoid sprout damage
- warm seed to 50-60degrees F for a few days before planting & plant in slightly cooler soil.
Don’t try to use potatoes from the vegetable section of the supermarket because they may be diseased, and they probably have been sprayed with a chemical to inhibit sprouting.
How TopVeg Chit Potatoes
Chits are the sprouting shoots that grow out of the eyes of a potato.
Gardeners encourage these chits to grow before the potatoes are planted, so they have a heads start when they are put in the ground.
Maris Bard seed potatoes have been chitting for a week.
- The seed is in an egg tray.
- The scar-side (point where the tuber was attached to parent plant) is down,
- with rose uppermost.
- The majority of eyes (buds) will be around the rose, and so pointing upwards.
- The tray is on a north-facing, light, frost free window sill.
- The chits (shoots) need to grow slowly.
- The light keeps the shoots short, fat and green.
- 4 degrees Celsius is ideal, but the temperature should not go above 10 degrees, neither should it reach freezing.
Chitting potatoes must be done properly, according to John Sarup of the SAC.