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Cover when about −5 °C holds for several days in a row: usually at the end of November or the beginning of December. Soil, straw, spruce branches or panels will do — with ventilation and protection from rodents. Uncover gradually, when the average daily temperature is steadily above +5 °C.
1Does your grapevine need cover
Most varieties in our catalog need cover: their frost-resistance limit, for example “down to −23 °C”, is lower than the frosts that occur in cold winters. Cover-free varieties (the variety page says “no cover”) overwinter without cover in typical winters, but there are two exceptions.
- Young bushes in the first 2–3 years are covered for all varieties, including cover-free ones.
- Severe, low-snow winters. If frosts stronger than the variety can withstand are forecast, cover protects mature bushes too.
You will find the frost-resistance limit of each variety on its page in the catalog.
2When to cover
Do not rush: the vine needs to harden off. Grapes tolerate the first light frosts — roughly down to −5…−8 °C — and this is how they harden: the vine ripens and turns light brown. Go by the weather, not the calendar: cover when about −5 °C holds for several days in a row. In central Ukraine this is usually the end of November or the beginning of December.
Covering too early risks rotting under cover, and too late — freezing. So the forecast matters more than the date.
3Preparing the vine for cover
- Prune the bushPruning is done after the leaves fall and before covering; remove weak and unripe shoots.
- Treat the vineMany growers spray the vine with an iron sulfate solution or other preparations against diseases and pests after leaf fall — before covering this lowers the risk of disease in damp conditions.
- Bend the vine to the groundLay it on a bedding (boards, grates or a layer of dry leaves) and pin it with staples so it does not spring up.
4What to cover with
| Method | How to do it | What to watch for |
|---|---|---|
| Soil | Sprinkle the vine with a 10–20 cm layer of soil | Take soil from between the rows, not from under the bush, so as not to expose the roots |
| Straw | A layer of straw of at least 20 cm | Straw attracts rodents, so protection from them is needed |
| Spruce or pine branches | A 30–40 cm layer, with agrofibre on top if desired | Branches ventilate well and attract fewer rodents |
| Panels and agrofibre | Boards, slate or roofing felt in the form of a “little house”, fill the space between bushes with straw or branches | Be sure to leave ventilation openings |
| Snow | A snow layer of over 50 cm | Unreliable in low-snow winters, so do not rely on it as the only cover |
Do not cover the vine with dense film without ventilation: condensation appears under it, and the vine rots or becomes covered with mold.
5Protection from rodents
Mice like dry cover made of straw or leaves. Place rodent baits under the cover (carefully: in places inaccessible to pets), and use straw only as a layer with enough ventilation. Check for rodents before you finally close the vine, and inspect it in spring: rodents can damage the shoots.
7Common mistakes
- Covering too early — before the vine has hardened off — and rotting under cover.
- Covering a wet vine and no ventilation.
- Straw without protection from rodents.
- Uncovering too early in spring, when frosts are still possible.
- Trying to do without cover for young bushes in the first years.
8Frequently asked questions
Do cover-free varieties need cover?
Young bushes — yes, in the first 2–3 years. Mature cover-free varieties overwinter without cover in typical winters, but in especially severe and low-snow winters cover insures against winterkill.
What is better to cover grapes with — soil or straw?
Soil cover is reliable and simple but needs a shovel and time. Straw is lighter but requires protection from rodents and ventilation. Spruce branches “breathe” well and attract fewer rodents.
When to remove the cover?
A guide is a steady temperature above +5 °C, soil at about +8 °C at a depth of 10–15 cm, and no frost forecast for the next 7–10 days. Remove it gradually, not in a single day.
