Biological features and agrotechnical requirements for growing forage carrots

Biological characteristics and growing requirements

Fodder carrot significantly surpasses fodder beet, swede, and turnip in terms of dry matter, carbohydrate, and vitamin content. It is a valuable source of carotene, with red-orange roots being the richest. The crop also contains vitamins B1, B2, PP, C, and mineral salts, which include calcium, iron, and phosphorus.

Fodder carrot (Daucus carota L.) is a biennial plant of the Apiaceae family. In the first year of life, it forms a leaf rosette and a root crop, and in the second year, after vernalization, it produces branching flowering stems 1–1.5 m high. In the first year, the growing season lasts 110–120 days (technical maturity occurs on day 80–90), and in the second year, it lasts 110–130 days. The inflorescence is a compound umbel of hermaphroditic white flowers, the flowering of which lasts 10–15 days.

The current list of carrot cultivars includes 53 names. Among them are Riga R3, Anastasia, Bangor, Bolero, Dordogne, Cupar, Maestro, Monanta, Nigel, Nandrin, Nanda, Nanko, Nectar, Panther, Paulinka, Rosal, Royal Forto, Topaz, Flam, Chantenay Red, Chantenay 2461, Shatriya, Yukon, and others. Cultivars with shortened roots mature faster and are significantly more convenient during harvesting than long and fusiform shapes.

Carrots are long-day plants and are characterized by high cold resistance. Their seeds begin to germinate in moist soil at a temperature of 3–4 °C, with emergence occurring after 15–20 days (the process accelerates at 18–20 °C). Young plants can withstand spring and autumn frosts down to −3…−5 °C. The crop prefers light loamy and sandy loam chernozems rich in lime. On dense, heavy soils, the roots become deformed, smaller, and branched, and on acidic, waterlogged, and saline areas, carrots grow extremely poorly.

In terms of drought resistance, carrots outperform other root crops but require good moisture during the period of seed germination and active root growth. An optimal water regime is also important for the rooting of seed plants in the second year of life. In the wild, the crop is still found in meadows and fields of the southern regions, in Central Asia, and in Central and Southern Europe.

Cultivation technology and sowing

The best areas for planting carrots are those that previously held winter cereals, grain legumes, or potatoes. The main condition for high-quality tillage is deep autumn ploughing to 25–35 cm, performed in the autumn. In the spring, the field is carefully prepared to create a loose, weed-free seedbed.

The fertilizer application system for carrots is similar to the nutrition of fodder beet. The main part of nitrogen, phosphorus, and potassium fertilizers (such as sylvinite and kainite) is applied in the spring. The greatest yield increase is provided by the combined use of organic and mineral fertilizers, while on podzolic soils, liming and top dressing show high efficiency.

1. Seed calibration to ensure uniform sowing.
2. Soaking of seed material.
3. Partial vernalization of prepared seeds.
4. Pelleting to protect seeds and improve their sowability.

Early sowing into moist soil is the key to obtaining uniform and quick emergence. In practice, winter sowing is also used, calculated so that the seeds do not have time to germinate before winter sets in. Sowing is carried out in a single-row method with row spacing of 45 cm or a double-row ribbon method (distance between ribbons is 50 cm, between rows is 20 cm).

• Seed germination temperature — 3–4 °C
• Frost resistance — down to −3…−5 °C
• Depth of autumn ploughing — 25–35 cm
• Seed application rate — 4–6 kg/t
• Seed sowing depth — 2–3 cm

Completion of carrot care and biological characteristics of swede

Care for fodder carrot crops includes post-sowing rolling, harrowing before and after emergence, and timely thinning. Roots are harvested with beet harvesters immediately before the onset of frost. Due to their deep placement in the soil, carrot roots are well protected from the first cold spells, so there is no reason to fear damage in the field.

Rutabaga (Brassica napus ssp. rapifera Metzger.) is a biennial cross-pollinated plant of the Brassicaceae family of European origin. In terms of dry matter content, it is inferior to beet and carrot, but superior to turnip. Rutabaga root crops are protected by a thick skin, which allows them to be stored excellently during the winter period.

• Minimum seed germination temperature — 2–3 °C
• Frosts tolerated by seedlings — more than 2–3 °C
• Dangerous autumn frosts — 6–8 °C
• Growing season in the first year — 110–130 days
• Weight of 1000 seeds — 2.5–4 g

The crop is demanding of moisture and does not tolerate drought well; however, excessive soil moisture also negatively affects the yield. Rutabaga prefers cohesive soils with good water-holding capacity, grows successfully on heavy and waterlogged plots, but is unsuitable for cultivation on sandy lands. During a prolonged cool spring, plants may flower as early as the first year due to a short vernalization stage.

Agrotechnology of rutabaga and biology of turnip

Regarding requirements for crop rotation, tillage, and the basic fertilizer system, rutabaga is similar to fodder beet and carrot. The Krasnoselskaya cultivar, as well as the time-tested Kuusiku cultivar, have become widely used in farms. On acidic podzolic soils, high efficiency is achieved through liming.

Rutabaga needs increased doses of potassium due to its poor absorption by the root system, but it effectively absorbs phosphoric acid. When sowing, it is recommended to apply granular superphosphate in the rows at a rate of 5–10 kg of active ingredient per 1 hectare. Sowing is carried out at the earliest possible time using a wide-row scheme.

• Row spacing — 50–60 cm;
• Seeding rate — 3–4 kg/ha;
• Sowing depth in the moist layer of soil — 2–3 cm.

Planting of rutabaga mother plants is carried out at an early stage using a square method according to a 60x60 or 70x70 cm scheme, with one plant per nest. The plot for seed crops is prepared in the autumn. As they grow, flower-bearing stems must be tied up; otherwise, they easily lodge due to their fragility. Seed rutabaga is harvested and stored just like other root crops.

Turnip, or fodder turnip (Brassica rapa ssp. rapifera Metzger.), is a biennial of the Brassicaceae family. In the first year, it forms a thickened root crop with succulent white or yellow flesh and a basal rosette of large, rough leaves without a waxy coating. Depending on the cultivar, root crops can be cylindrical, oval, or spherical. The upper part of the root crop is colored violet or white, the lower part is always white, and lateral roots develop only on the tapered lower end.

In the second year of life, turnip produces flowering shoots with triangular stem-clasping leaves and yellow flowers in the form of a raceme. The fruit is a pod containing about 20 small round brown seeds. The weight of 1000 turnip seeds is 1.5–3.5 g.

Compared to beet, carrot, and rutabaga, turnip root crops are more watery and have loose flesh. It is a high-yielding, cross-pollinated long-day crop that is demanding of light but less fussy about soil fertility than other root crops. Due to this, turnip is cultivated even up to the northern borders of agriculture.

To improve storage life, choose yellow-fleshed cultivars: they accumulate more dry matter, although they are slightly inferior to white-fleshed ones in terms of yield. When planning cultivation, consider that drought and heat depress the plants, leading to the formation of small and less succulent root crops. The crop shows the highest productivity in conditions of a cool summer with frequent rains, mists, and dews.

• Growing season in the first year — 70–110 days
• Growing season in the second year — 85–90 days
• Minimum seed germination temperature — 2–3 °C
• Frost resistance of seedlings — down to −3...−5 °C
• Frost resistance of adult plants — down to −7…−9 °C
• Seeding rate — 3–4 kg/ha

Soil requirements and sowing technology

Turnip is less demanding of soil conditions than rutabaga. It can be cultivated on podzolic loams, drained swamps, and peatlands. Moderately moist loamy and sandy loam soils with high humus content are considered the best for it.

The crop does not grow well on the following types of soil:

• very heavy;
• solonetzic;
• waterlogged;
• acidic (without prior liming).

Plants respond excellently to fertilizer, especially to the combined application of organic and mineral fertilizers. At the same time, regarding responsiveness to potash fertilizers, the turnip surpasses the swede.

1. Apply organic and mineral fertilizers during ploughing, paying special attention to potash grades.
2. Sow the seed directly into the soil from late May to mid-June, as the turnip does not tolerate transplanting.
3. Use a row sowing method with a row spacing of 45–60 cm and a sowing depth of 2–3 cm.
4. Carry out crop care and harvesting following the same technological scheme as for the swede.