Riparia Rupestris 4923 is a grape variety obtained by crossing two American wild species, Vitis riparia and Vitis rupestris. It has a powerful root system that penetrates deeply into the soil, providing the plant with moisture even in dry conditions. Thanks to this, the variety adapts well to various soil types, including sandy, rocky, and clay soils, making it versatile for cultivation in different regions.
The vines of this variety have medium growth vigor, with cane-like, upright dark brown shoots. The leaves are characteristic of the Riparia species: matte, dull, medium-sized, with a leaf blade curved along the central vein and wavy, upward-curving margins. The rootstock and bud hardiness of this variety is very high, allowing it to successfully overwinter under adverse climatic conditions.
Riparia Rupestris is highly resistant to phylloxera rootstock forms and fungal diseases such as mildew and oidium. However, the leaf form of phylloxera attacks the plant quite severely, so regular insecticide treatments are required. The berries of this variety have low sugar content and high acidity, making them more suitable for producing blended wines and juices, as well as serving as rootstocks for more demanding European grape varieties.
