Tea-hybrid Rose 'Juriadna'

Synonyms: Big Purple, rose Jurianda, Stephens' Big Purple

Tea-hybrid Rose Juriadna (Rose Jurianda) is a tea-hybrid rose cultivar. The cultivar was developed in 1985 by New Zealand amateur rosarian Pat Stephens, who was the secretary of the New Zealand Rose Society. The cultivar received the «Best Purple Rose» award in 1999 at the Rosexpo Montreal Show.

It is a vigorous, upright, robust shrub, 100–140 cm in height and 70–75 cm in width. Leaves are leathery, grayish-green.

Buds open slowly, appear singly on the shoots, cup-shaped. Flowers are very double, large, 10–12 cm in diameter. Petals are a deep purple color, velvety, 45 or more per flower. Fragrance delicate, rosy.

Hardiness zone: 7b (-12°C)

Site: choose a sunny, bright location sheltered from strong, cold winds. Flowers do not like rain, so it is preferable to plant in a dry site.

Soil: the most suitable soils for roses are heavy loams rich in humus, well aerated, moisture-retentive, slightly acidic (pH 5.8–6.5). Prepare the soil in autumn or at least one month before spring planting. It is very important to work the soil to a depth of 50–60 cm. Per 1 m2 of worked layer add 10–20 g of manure, humus or peat-compost, 300–400 g of lime, 400–500 g of bone meal, 40–50 g of superphosphate, 150–200 g of wood ash. Dig the soil, mixing it with the fertilizers; organic matter in the soil mix should not exceed 50%. The exact fertilizer rate is calculated based on soil analysis. The optimal content of major nutrients for roses should be maintained in the following amounts, mg per 100 g of soil: nitrogen – 10–20 (NH4NO3), phosphorus (P2O5) – 60–80, potassium (K2) – 80–100, calcium (CaO) – 720.

Planting: recommended to be done in the first half of the day. In temperate regions it is best to plant roses in spring – late April to early May; in the south – in autumn. Before planting remove all damaged and diseased shoots and roots from the seedling. Strong shoots are pruned short – to 10–15 cm, leaving only 2–4 buds on them. Trim roots slightly – to healthy tissue. If the roses were dried, place them in water for 24 hours before planting, and immediately before planting dip the roots into a manure-clay slurry. Planting holes are prepared 50x50 cm and filled with a nutrient mixture: 1 part turf-clay or garden soil, 1 part humus or compost – forming a mound. Place the seedling on the mound, spread the roots and cover with soil, tamping it well so there are no air pockets between roots and soil, and water abundantly. Bury the graft union 3–5 cm below soil level. After watering, hill up the roses. Protect the shoots from drying out. After shoots appear, rake the soil and mulch with humus or peat to a depth of 5–8 cm to help retain moisture. Spacing in a row for tea-hybrid, floribunda and polyantha roses is 25–30 cm, between rows 60–70 cm; for shrub and climbing roses 45–50 cm and 80–100 cm respectively; for miniatures 15–20 cm and 40–50 cm. When planting standard roses, to prevent drying, their grafted part is often packed with moss and wrapped in paper; this is removed only after 1–1.5 weeks, when buds begin to swell. After planting mulch the soil with peat or soil to a depth of 3–5 cm. When planting non-remontant shrub roses, mulch with pine bark or wood chips.

Care: requires regular pruning of shoots affected by pests and diseases, as well as removal of dead leaves. Watering is recommended during dry periods.

Pruning: performed in spring, summer and autumn. The main pruning is in spring, when the bush is formed. It begins immediately after the plants have fully emerged from winter or at spring planting. Cut the top parts of shoots regardless of the cultivar; strong shoots are shortened to 10–15 cm, leaving 2–3 well-formed buds, weak shoots – 1–2 buds. For autumn plantings pruning is done in spring, immediately after removing the winter protection. To encourage abundant flowering, remove old flowers.

Propagation: mainly by grafting and cuttings. Cuttings are taken during bud formation or immediately after the first flowering. Shoots are cut from the bush and cut into cuttings 5–8 cm long from the central part with 2–3 leaves. Make the lower cut just below the bud at an angle, and the upper cut 1 cm above the bud. To reduce transpiration, remove the lower leaf and part of the upper one. Leaves should be handled carefully; do not remove them completely, as cuttings do not root without them. Before planting, place cuttings for 18–20 hours in a rooting stimulator, immersing the ends 1–1.5 cm. This can be a 0.01% solution of heteroauxin. You can also use Rootin, sodium humate (1 tablet per 1 l of water), aloe (10 drops per glass of water) or honey (1 teaspoon per glass of water). Then rinse the cuttings with clean water and plant. Plant cuttings in a box or bed. The bed should be located where it receives sun in the morning or evening, and shade at midday. As a substrate, coarse river sand, a mixture of vermiculite with sand, or sand with peat (1:1) is usually used. This substrate, 3–4 cm thick, is placed over turf-humus soil (8–10 cm). Plant cuttings at an angle, burying them 1.5–2 cm deep. Then cover in the bed with glass jars or cover the box with film. After planting, moisten the cuttings several times a day, preferably with a sprayer, maintaining humidity at 80–90%. Remove fallen leaves. After 2–3 weeks a callus appears on the cuttings, and roots form in about a month. Remove jars or film, and grow the cuttings on, feeding every 2 weeks with a solution of ammonium nitrate or urea (15–20 g per bucket of water).

Diseases: may be affected by powdery mildew and black spot.

Pests: aphids, scale insects, leafrollers, rose sawfly, thrips, rose cicadas, inchworm caterpillars, cutworms, spider mites, nematodes. It is recommended to regularly spray tea-hybrid roses with appropriate products for pest protection.

Uses: makes an impressive display in mixed borders, as a solitary planting, or at the front of flower beds. Suitable for cutting. Valued for its dark, intense color.