Growing stubble turnips, for livestock forage, is a cost-effective way to provide nutritious feed. In this article, I outline the steps I take to establish a decent crop.
Field selection
Choose a field with good drainage and a pH between 6.0 and 7.0. Swedes thrive in fertile, loamy soils. I would then do a soil test and then decide how I was going to amend the soil to meet the demand of the crop.
If I wanted to add farmyard manure I would add it to the land before ploughing, if I was using fertiliser I would add it after the seeds are sown. Farmyard manure should be completely buried otherwise the sower coulters will block.
Seed selection
Opt for disease-resistant and high-yielding varieties suitable for your region. Consider the maturity rate to align the harvest with your livestock’s forage needs.
Soil preparation
After ploughing I would power harrow the field to create a fine, firm seedbed. This preparation promotes good seed-to-soil contact, which is essential for good germination.
Sowing
I would sow the seeds using my precision sower on the flat cultivated soil. Sow seeds at a depth of 1-2 cm, spacing 6 inches along the row and each row approximately 30 cm apart. For smaller areas, broadcasting by hand is viable but ensure even coverage.
I would aim to sow seeds from late April to early June to allow for autumn and winter grazing.
Fertilisation
Apply a balanced fertiliser based on soil test recommendations at sowing. Swedes respond well to nitrogen, phosphorus, and potassium. A split application of nitrogen after establishment may boost growth.
Weed control
Implement weed control measures early. If the field is known to have a lot of weeds I would burn it off with glyphosate a month before ploughing. Use a pre-emergence herbicide like Butisan to suppress the weeds until your seedlings get stronger.
Mechanical weeding can also be used but it is quite tricky because of the close row spacing to remove weeds without damaging the young swede plants.
Pest and disease management
Monitor for common pests like cabbage root fly, and flea beetles, although there is little you can do about the cabbage root fly other than using a net which is not applicable for stubble turnips. Flea beetles can be controlled with insecticides and fungicides may be necessary for powdery mildew or clubroot, depending on prevalence.
Irrigation
It would be highly unusual to see irrigation in a field of stubble in turnips in Northern Ireland, we usually have enough rain to get through dry periods. The stubble turnips do like to have plenty of moisture, especially during germination.
Swedes require 1 inch of water per week, either from rainfall or supplementary irrigation.
Harvesting
Stubble turnips are ready for grazing approximately 10-12 weeks after sowing. I have found strip grazing is the best way to manage forage consumption efficiently and reduce wastage.
Post-harvest management
After grazing, consider planting a green manure crop to protect and enrich the soil. This practice also helps in breaking pest and disease cycles.
For a green manure crop following stubble turnips, field beans (Vicia faba) are an excellent choice. Field beans fix nitrogen, improving soil fertility for the next crop. They also provide good ground cover, reducing weed growth and soil erosion. Sow in autumn after harvesting turnips for a winter cover, then incorporate into the soil before flowering in spring for the best nitrogen-fixing benefits.
Growing stubble turnips for livestock forage offers a flexible and nutritious feeding option. With proper planning and care, your field can provide valuable feed during the colder months when other forage may be scarce. They require minimal field cultivations and are quick to grow. Stubble turnips are an excellent break crop to add to your crop rotation.
