What Is Chitting and Why Bother For Early Potatoes?
Chitting, also known as sprouting, is the process of encouraging seed potatoes to develop short, sturdy shoots before planting. For first early potato varieties, this step is particularly beneficial. By chitting, you give your potatoes a head start, ensuring they are ready to grow vigorously as soon as they are in the ground, especially when tackling cooler spring conditions.
- Chitting primes seed potatoes for faster growth.
- It's vital for maximising yields from early varieties.
- Develops sturdy sprouts, not weak, leggy ones.
- Prepares potatoes for planting in cooler soil.
The primary aim is to promote the formation of short, stubby sprouts from the 'eyes' of the potato. These sprouts are essentially the plant's initial growth points. When done correctly, chitting leads to earlier tuber formation and a quicker harvest, which is precisely what you want from 'first early' types. Without chitting, especially if planting conditions are less than ideal, your potato plants might take longer to establish, potentially delaying your harvest or reducing overall yield.
It's not just about getting sprouts; it's about getting the right kind of sprouts. Long, wispy, pale sprouts are a sign that the seed potatoes have been kept in the dark and are reaching for light, indicating they've been stored too long before chitting. These are weaker and more prone to damage during planting. Well-chitted potatoes, conversely, will have short, thick, dark green or purple sprouts, depending on the variety, ready to push through the soil with vigour.
The "first early" classification tells us these varieties are bred for speed. They mature relatively quickly, often within 10-12 weeks of planting. To achieve this rapid growth cycle and secure an early harvest, preparing the seed potatoes through chitting is a key strategy. It effectively fast-forwards the initial growth phase, allowing the plant to focus its energy on developing tubers sooner.
Understanding Seed Potato Varieties
Before delving into the 'when', it's useful to know that potatoes are generally categorised by their maturity times: first earlies, second earlies, and maincrop. First earlies are the quickest to mature, followed by second earlies, and then maincrop varieties which take the longest. Each category benefits from chitting, but the timing and expected outcome are most pronounced for the first earlies, as they have the shortest window to deliver their crop.
The quality of your seed potatoes also plays a significant role. Always source certified seed potatoes from a reputable supplier. These are guaranteed to be disease-free, which is fundamental for healthy plant development and a good yield. The size of the seed potato itself can also influence the number of sprouts. Larger seed potatoes typically have more eyes and therefore can produce more initial shoots, though the goal remains robust, not necessarily numerous, sprouts.
When to Start Chitting First Early Potatoes
The crucial question: when to chit first early potatoes? The general rule of thumb is to begin chitting your seed potatoes approximately 4-6 weeks before your intended planting date. For first earlies, this typically means starting the process in late winter or very early spring.
Start chitting your first early seed potatoes 4-6 weeks before you plan to plant them, usually from February onwards for outdoor planting.
Consider your local climate and the prevailing weather conditions. While you want to get a head start, planting too early into cold, waterlogged soil can be detrimental. The aim is to have the potatoes well-chitted and ready to go into the ground when the soil temperature has warmed sufficiently and the risk of hard frosts has significantly diminished. For most regions in the UK, this planting window for first earlies often falls between late March and April.
Therefore, if you're aiming to plant your first early potatoes in late March, you should begin chitting them from early to mid-February. If your planting date is more likely to be in April, then starting the chitting process in late February or early March would be appropriate. It’s about synchronising the chitting period with the readiness of the soil and the end of winter's harshest weather.
The Chitting Environment
The ideal environment for chitting is a cool, bright, frost-free location. A windowsill in an unheated room, a greenhouse, or a conservatory are often perfect spots. The temperature should ideally be between 8°C and 15°C (46°F to 59°F). Too warm, and the sprouts will grow too quickly and become weak and leggy. Too cold, and the process will be significantly delayed or may not happen effectively.
Light is also essential. While you don't want direct, scorching sunlight, a good amount of indirect natural light helps develop those desirable short, sturdy, dark sprouts. Avoid storing seed potatoes in completely dark conditions during the chitting phase, as this encourages the weak, pale growth that is undesirable. Good light exposure also helps to harden the sprouts, making them more resilient.
Use shallow trays, egg boxes, or old seed trays to hold the potatoes. You can lay them in a single layer, or if stacking, ensure there is adequate air circulation. The aim is to give each potato enough space and exposure to light and air to encourage even sprouting.
How to Implement the Chitting Process
Achieving successful chitting involves a few straightforward steps. Once you've decided when to chit first early potatoes, you need to prepare your seed potatoes and the chitting location.
First, acquire your certified seed potatoes. Ideally, do this a few weeks before you intend to start chitting, allowing them to acclimatise to room temperature. Some growers like to 'green' their potatoes for a week or two beforehand by exposing them to light, which can help prevent tuber blight and encourage earlier sprouting.
Next, arrange the seed potatoes in your chosen trays or containers. Place them 'rose end' up, where the majority of the eyes (the little dimples from which sprouts emerge) are located. You don't need to cover them with soil or compost; they simply need to be laid out so they don't touch each other too much and have good access to light and air. Egg boxes are surprisingly effective for this, as they keep the potatoes separated and upright.
Monitoring and Care During Chitting
Keep an eye on your potatoes throughout the chitting period. You should start to see small sprouts emerging from the eyes within a couple of weeks. If any potatoes show signs of disease, such as rot or mould, remove them immediately to prevent it from spreading to healthy ones. Ensure the environment remains cool, bright, and frost-free. Occasional misting with water might be beneficial in very dry conditions, but avoid making the potatoes waterlogged.
The sprouts should be short, thick, and a healthy green or purplish hue. If they are becoming long, thin, and pale, it indicates the conditions are too dark or too warm. You might need to move them to a brighter, cooler spot. Resist the temptation to break off excess sprouts; leave them to develop naturally.
By the time you're ready to plant, your seed potatoes should have several well-formed sprouts, typically around 1-2.5 cm in length. These are now primed and ready to be carefully planted into their final growing positions, whether that's in the ground, in growing bags for potatoes, or in pots.
The success of your early potato harvest hinges on preparing your seed potatoes correctly.
When handling chitted potatoes, be gentle. The sprouts are still delicate and can be easily damaged. This is why it's important to get the timing right – you want them to have developed good sprouts but not outgrown them to the point where they are cumbersome and fragile.
Alternatives to Traditional Chitting
While the tray method is standard, some gardeners experiment. For instance, some growers place seed potatoes in paper bags with a few holes poked in them, storing them in a cool, bright place. Others might use old potato sacks or even keep them in their original packaging if it allows for light exposure and air circulation.
The core principle remains: provide cool, bright conditions and allow the eyes to sprout. The method is less important than the environment. For those with limited space, growing potatoes in pots or containers is a viable alternative, and the chitting process remains the same prior to planting them in their pots.
Planting Chitted Potatoes and Next Steps
Once your first early potatoes are well-chitted and your soil is ready, it's time for planting. The ideal soil conditions are moist but not waterlogged, and a temperature of at least 7°C (45°F). Aim for a sunny, sheltered spot.
When planting, dig trenches or individual holes about 10-15 cm (4-6 inches) deep. Place the chitted seed potatoes 'rose end' (sprout end) upwards, spaced about 30 cm (12 inches) apart. If planting in rows, leave about 45-60 cm (18-24 inches) between rows to allow ample space for growth and earthing up.
Cover the potatoes with soil, creating a small ridge. As the potato plants grow, you will need to 'earth them up' by drawing soil from between the rows around the base of the stems. This process encourages more tubers to form and protects them from sunlight, which can turn them green and inedible. Repeat earthing up a couple of times as the plants grow taller.
When to Plant Potatoes
The exact date for planting potatoes varies depending on your location and the specific year's weather. For first earlies, planting typically begins from late March onwards, extending through April. It's always advisable to check your local weather forecast and soil conditions before committing to a planting date. Cold, wet soil is the enemy of newly planted potatoes.
The key is to avoid planting before the danger of hard frost has passed and the soil has begun to warm. If you are concerned about late frosts, you can delay planting slightly or use horticultural fleece to protect emerging shoots.
For those growing potatoes in bags or containers, the timing can be a little more flexible. You can start them off in a greenhouse or sheltered patio earlier, protecting them from frost, and then move them to their final growing position once the weather is more favourable.
Monitoring Growth and Anticipating Harvest
After planting, keep the soil moist, especially during dry spells. You'll see the first shoots emerging from the soil within a few weeks. Continue earthing up as the plants grow. First early potatoes typically mature around 10-12 weeks after planting. Keep an eye on the plants; they will usually start to flower, which is a good indicator that tubers are forming below ground.
When the potato plants start to die back and the flowers fade, it's a sign that the tubers are nearing maturity. For an 'early' harvest of new potatoes, you can gently dig around the base of a plant with your hands or a fork to check the size of the tubers. If they are large enough for your liking, you can carefully lift some or all of the crop. If you want larger potatoes, leave them for another week or two.
The process of chitting ensures that when you plant, your potatoes are already primed for rapid growth, giving you the best chance of a delicious early harvest from your first early potato varieties. Enjoy the fruits of your early planning!
Troubleshooting Common Chitting Issues
Even with careful planning, gardeners sometimes encounter problems during the chitting process. Understanding these issues and their solutions can save your seed potatoes and ensure a successful crop.
Weak, Leggy Sprouts
The most common issue is the development of long, thin, pale sprouts. This almost always indicates insufficient light or excessive warmth. If you notice this happening, move your seed potatoes to a brighter, cooler location immediately. While you can't 'un-lengthen' them, ensuring subsequent sprouts are short and sturdy is key. These leggy sprouts are more susceptible to damage during planting, so handle them with extreme care.
No Sprouts Appearing
If, after several weeks, you see no sign of sprouting, several factors might be at play. The seed potatoes themselves might be old or of poor quality. Ensure you purchased certified seed potatoes from a reliable source. The temperature might be too low; while a cool environment is good, it shouldn't be near freezing. Also, check if the potatoes are consistently dry – a little moisture can help initiate sprouting, but they shouldn't be waterlogged, which leads to rot.
Rotting or Mouldy Potatoes
This is a more serious problem and often stems from poor air circulation or excessive moisture. Seed potatoes that are stored in sealed plastic bags or kept in damp, unventilated conditions are prone to rotting. If you spot any signs of rot or mould, remove the affected potato immediately. Discard it away from your garden to prevent disease spread. Ensure good airflow around the remaining potatoes and try to maintain a slightly drier environment if rot is becoming prevalent.
Damage to Sprouts
Once sprouts have formed, they are vulnerable. Accidental knocks, dropping trays, or even enthusiastic pets can cause damage. If only a few sprouts are damaged, the potato will likely produce new ones from other eyes. However, if the main sprout on an entire potato is severely damaged, that specific potato might be compromised in terms of its early growth potential.
To prevent sprout damage, handle trays with care and consider using containers like egg boxes that naturally protect the emerging shoots. If you notice damage during the chitting phase, assess the extent. Minor damage may not be critical, but severe damage to all sprouts on a potato might mean it's best to reserve it for later planting or discard it if the damage is extensive.
Alternative Varieties or Planting Times
If your chitting is delayed or you've encountered issues, don't despair. You can still achieve a good harvest with second early or even maincrop varieties, though they will mature later. You can also adjust your planting schedule. If the weather is poor, it's often better to wait a week or two longer to plant than to put seed potatoes into unsuitable soil. The goal is to have the potatoes ready when the soil conditions are optimal for their growth, ensuring the best possible outcome for your potato plants.