In the Calçot Cultivation Guide we show you that calçots are the shoots that grow from a late white onion which is the white onion of Lérida or Lleida. However, its cultivation is very common in the interior of Catalonia. It is traditional throughout the western area where it is consumed from the end of winter until April, although the beginning and end of harvesting may vary according to the area.
Although it is an autochthonous crop, it acclimates very well to different climates and locations in Spain and so you can grow them in your family garden or urban garden as long as you have cool winters without strong frosts, that is, if you have a climate with mild winters.
WHEN AND HOW TO PLANT
According to our Calçot Cultivation Guide, the ideal time for its cultivation is from the end of summer until the beginning of winter. If we carry out a staggered planting, we will be able to harvest it at different times and thus be able to enjoy this delicacy for a longer period of time.
Before planting the Calçots I recommend you to fertilize the soil with worm castings, decompact the soil well and mix until you notice that the soil is loose.
Once we have the soil ready we proceed to make some furrows that are at least twice the size of the bulbs that we put approximately 25-30 centimeters would be more than enough. Remember to leave a distance of 20 centimeters between Calçots and 50-75 centimeters between lines.
Make sure that the placement is correct. This is always with the tip upwards and the flat part downwards, which is where the roots will come out. Once we have this clear we give a good watering to the area where we place the bulbs and introduce them into the soil at least 1/3 of its size is buried,
In the Calçot Growing Guide we tell you that it is not a very demanding plant in terms of irrigation, with a couple of weekly waterings we will have more than enough and if we have rains it would not be necessary to water while the soil is moist. Remember that an excess of water could rot the bulbs.
In our Calçot Growing Guide we show you that for irrigation we can opt for both the exudative hose and the dripper hose if we have mains water. If not, we can fill the ridges with water by the flooding method.
SHOEING OR SHOEING OF THE SHOOTS
This is the reason for its name Calçot is calçot in Spanish and this is one of the tricks to consume quality calçots that we teach you in the Cultivers Guide to Calçot Cultivation.
As the sprouts grow, we have to wedge them with the soil that we have on both sides. Creating a small mountain that covers the stem almost completely, you will have to do this whenever you see that the stem is already at least 30 cm and leaving 1/3 out of the ground and repeating as many times as the plant asks us. I usually do it 4 to 5 times.
Keep in mind that the part that remains covered will be the white part of the sprout that is consumed. So the more sprouts we cover, the more we can consume.
HOW AND WHEN TO HARVEST
And now in the Calçot Cultivation Guide we come to the part that we like the most of the crops, the harvest. Normally you can begin to collect from 4 months when the bud is already as fat as the ring finger, although for this tastes colors, there are people who like them thinner for consumption.
We have to hurry and avoid flowering as this reduces the quality of the Calçot unless we want to leave a plant for seed and perform the complete cycle of this curious onion.
With respect to how to harvest, it is very simple, we only have to pull up or pry up with a pitchfork and we will obtain the precious fruit of our work.
We can let them dry to the maximum on the plant to save seed for next year and thus have a seed that will have in its genetic memory our soil and climate, so it will develop better.
COMMON DISEASES AND PESTS
- Onion beetle(Lylyoderys merdigera). The adults are 7 mm long, cinnabar-red coleoptera, while the larvae are small and yellow. It is a pest that occurs during the spring. The adults lay their eggs on the leaves and their larvae cause damage by cutting parallel bands along the nerves of the leaves. Before reaching the nymphosis stage, they bury themselves in the soil or substrate, where they are produced, until the adult matures and emerges. It is a pest that we must take into account since it can have two annual generations.
- Onion fly(Hylemia antigua). A yellowish-gray fly of about seven millimeters, with five characteristic dark lines on the thorax, yellow wings with black legs and antennae. Each adult lays about 150 eggs that hatch in about 22 days. As in the previous case, it overwinters in the soil in the pupal stage. The first generation appears with the arrival of good temperatures… at the end of March or early April depending on the geographical area where we are. After two weeks, the clutches begin to lay singly or in groups of about 20 eggs near the neck of the plant, on the ground or on scales. Larvae appear after five days and up to five generations can occur per year if the weather is favorable. As for the damage, it produces them throughout the plant: in the apex of the leaf that pales and then dies, rotting the affected parts of the bulbs and in flowers it damages them so that they abort without the possibility of obtaining seeds.
- Onion moth(Acrolepia assectella). In its adult state, it is a small butterfly with a wingspan of only 15 millimeters. It can be easily distinguished because its forewings are olive-blue with small ochre-yellow scales, while the hind wings are grayish. The larvae are almost two centimeters long, yellow with a brownish head. Laying by the female butterflies takes place at the end of May and the larvae penetrate inside the plant as soon as they flutter, producing holes in the leaves. These caterpillars move inside the leaves until they reach the bulb, eventually causing rotting as a result of secondary infections caused by fungi.
- Nematodes(Dytolenchus dipsaci). These can attack onions or calçot at any stage of plant development, although mainly on the youngest tissues. If they are in the seedling stage, they stop growing, curl and lose color. If the bulbs are more developed, their tissue softens near the top. In all cases the crop is significantly reduced.
- Thrips (Frankliniella occidentalis) Thrips are elongated insects measuring about 1- 2 mm (visible to the naked eye and recognizable with a magnifying glass) and are brown in color. These insects suck plant material from the tomato plant. The area where it has been suctioned presents a silvery coloration and eventually necroses.
- Blight(Urocystis cepulae). This disease also frequently attacks garlic, chives and leeks. It is a soil-borne disease. Infection begins by attacking the first young leaves near the soil surface. Once the seedling is infected, the fungus spreads throughout the seedling. The symptoms of Urocystis cepulae attack manifest themselves in the form of lead-colored bands which, when they burst, give off black powdery masses composed of spores. These spores fall to the soil and leave it contaminated and useless for onion planting for a long period of time.
- White tip(Phytophtora porri). It also attacks leeks and garlic. The tips of the leaves of affected plants become white in appearance, much as if they were bleached by frost. These infected leaves rot and eventually the entire plant rots as well. As a cultural measure, it is recommended to rotate the crop and not to repeat it in the same field for three years in the case of an attack.
- Botrytis(Botrytis squamosa). Characteristic yellow-white spots appear all over the leaf. When the attack is severe, leaf necrosis occurs and the plant dies. It favors humidity and low temperature conditions.
- Alternaria(Alternaria porri). Affected plants initially show whitish lesions on the leaf that immediately turn brown. When the fungus sporulates these lesions take on a purple hue.
- Downy mildew(Peronospora destructor or schleideni). Warm and humid weather favors the development of this disease, which appears on new leaves with elongated spots covered with a purplish felt. If the attack persists and is not controlled, the tops of the plants die off completely and the bulbs fail to mature. Downy mildew is spread by the bulbs in the case of calçots, by the seeds or by the soil. One of the efficient cultural measures for its prevention is to grow onions on light, loose and well-drained soils.
- Rust (Puccinia sp.). Rust attacks all group plants such as leeks, chives, etc., the most sensitive of all being garlic. Its first symptoms appear at the beginning of May and originate reddish-brown spots that later turn purplish, in which uredospores develop. Affected leaves dry out prematurely and even cause the plant to stop growing.
- Onion charcoal(Tuburcinia cepulae). In the beginning, silvery-gray streaks begin to appear, which eventually become black. If the attack occurs at the seedling stage, the affected plants die. The attack begins with seed germination because the fungus persists in the soil crop after crop.
- White rot(Sclerotium cepivorum). Affected plants are covered with a kind of white cottony felt in which sometimes small sclerotia can be seen on the surface of the bulbs. Attacks are focused both at the time of sprouting and as harvesting approaches. As a consequence of root damage, its leaves turn yellow and finally the plant dies.
- Onion variegated. This is a disease caused by a virus transmitted by several species of aphids. After infection, the leaves become paler green and long yellow streaks appear. As a consequence, plants weaken and die.
PRODUCTS WE RECOMMEND FOR THIS CROP