Salvia plant (lat. Salvia), or sage, is a large genus of herbaceous perennials and shrubs of the family Labiatae or Lamiaceae, common in tropical and temperate regions of all parts of the world except Australia. The name “salvia” is derived from the Latin word “salvus” meaning “to be healthy”, and this is due to the fact that some species of the plant have long been used for medical purposes. Nothing heals a dental abscess so quickly but a gargle with decoction of sage. There are only about 900 representatives of salvia genus, and they prefer to grow in bright places. To avoid confusion, a medicinal plant and a spice are commonly called “sage” while ornamental plants of this genus are called “salvia”. Although salvia is sage as well, but it is used mainly for decorative purposes. Sage was known since Roman times, but salvia flowers were brought to Europe only in the XVIII century when there was the era of the gardening boom. Salvia divinorum, or diviner’s sage, stands apart from the other species in the classification. It is used to extract salvinorin, psychoactive hallucinogen, from its leaves. But in this article we will focus on ornamental salvia shrubs.
- 1. Audio article (coming soon)
- 2. Description of salvia flower
- 3. Growing salvia from seeds
- 4. Planting of salvia
- 5. Salvia: care
- 6. Species and varieties of salvia
Description of salvia flower
Salvia flower is a rhizome perennial plant, but in our climate zone it is mostly grown as an annual or biennial plant. Some species can tolerate cold winters, but if the winter is snowless or with little snow, the plant can be nipped by the frost. The stems of salvia are erect or ascending, quadrangular, sometimes reaching a height of 4 ft. The leaves are entire, sometimes pinnatisect, arranged oppositely on the petioles, the upper side of the blade is dark green, the underside is whitish. Small flowers are collected into complex whorled spicate or paniculate inflorescences of 6-8 inches long at the ends of the stems. Brightly colored bracts are pink, white, lilac or purple. Fruit of salvia consists of four nutlets. Salvia seeds reach maturity within a month after the beginning of flowering and remain viable for up to five years.
When to sow salvia.
Annual and biennial salvia is grown from seeds, perennial salvia is propagated both by seeds and vegetatively – by cuttings or through bush division. Growing of salvia from seeds can be carried out both through seedling and non-seedling way. With non-seedling way applied, the seeds are sown in the soil before winter or in spring. But such species as scarlet sage, or tropical sage (Salvia splendens) is propagated exclusively through seedlings. Besides, in the plant nurseries you can find seeds and granules that in addition to seeds contain substances that make seedlings resistant and stronger, but granules sprout slower than normal seeds. When is the best time to sow salvia seeds? Sowing of salvia seeds in boxes is performed from mid-February to early March.
Seeds or granules are sown on wet loose soil surface or at a depth of no more than 0.08 inch and kept at a temperature of about 77 °F. Watering should be carried out in the tray or through the spray gun, and in order to keep the soil moist cover the box with paper. Seedlings appear within two weeks or a month. Your further task is to grow seedlings with a strong root system that will allow the plant to quickly take root in the ground. To achieve this, the seedlings are pricked out twice. The first time is when two or three true leaves appear, the shoots are transplanted into a box 2 inches apart and deepened into the ground at the level of cotyledons. For the second time the seedlings are transplanted into individual pots with a diameter of 4-4.7 inches in three weeks after the first picking out. When the third or the fourth true leaf is developed, the shoots are pinched out to promote bushy look. From April you can start getting seedlings adapted to the temperature outside by lowering a night temperature up to 50 °F.
When to plant salvia.
Salvia prefers light permeable sandy soil with a high content of lime and humus. The planting site should be sunny since all species of salvia are sun loving plants, and only sticky sage can grow in partial shade. Salvia seedlings are planted in the open ground only if there is no threat of night frosts, that is, around the beginning of June.
How to plant salvia.
Planting and care for salvia are easy tasks, even for novice gardeners. Besides hardy, healthy seedlings tolerate well transplantation into the garden. Before transplanting, add a handful of humus into each planting hole that should be dug out at a distance of 10-12 inches from each other.
How to grow salvia.
As any garden plant, salvia requires such garden works as watering, weeding, loosening the soil, feeding by fertilizers. All this work must be done on as needed basis. Water the soil when the ground beneath salvia is well dried out after previous watering, and only in the evening, but do not pour too much water, because the plant does not tolerate water stagnation at the roots. Some time after watering loosen the soil and remove weeds, if there are any. Combined mineral fertilizers are applied at least twice during the summer: for the first time feed the seedling with a weak solution, for the second time apply fertilizers during the formation of flower buds.
Perennial salvia will require more attention and efforts than annual or biennial salvia (grown from seeds sown before winter), since it needs shape-forming pruning for the shoots not to stretch and become bare. Besides pruning stimulates tillering and growth of young shoots. When perennial salvia fades, remove the withered flowers from the bush, and before the winter dormancy or early next growing season prune salvia: cut the old lignified shoots to leave branches only a few inches long with buds and young leaves.
Pests and diseases of salvia.
Salvia is affected by diseases so rarely that there is no sense to talk about this. As regards pests, the plant is sometimes attacked by whitefly, thrips, aphids and mites, as well as slugs and snails that eat tender leaves of salvia.
Snails and slugs have to be removed mechanically: gather them manually; put baits in the form of pieces of slate or rags under which slugs will crawl; put some cups with beer or fruit juice and cover them with sort of umbrella to protect the contents from rain and debris. Gastropods are attracted by a pleasant smell, and you will be able to collect a decent amount of these pests.
To fight with the insects use the insecticide that is relevant to each of the pests.
Salvia after flowering.
Salvia flowering begins in June and it blooms until autumn frost depending on the variety. Some salvias can bloom twice a year. For example, wood sage will bloom again in late summer if it is completely cut after flowering and especially if it is fed with a fertilizer. But if salvia fades, carry out fall pruning and mulch the site, and especially apical buds, with garden compost for the plant to safely overwinter. Young salvias need to be additionally covered with spruce branches or dry leaves.
According to agronomic and biological characteristics the scientists divide salvia species into three groups. The first group includes representatives of the American subtropics that are mainly grown as annuals. These species prefer moist soil and cannot tolerate even a light frost. The first group includes:
Scarlet sage, or tropical sage (Salvia splendens)
is a compact bush with a rich foliage and a height from 8 to 31 inches. The leaves are opposite, entire, ovate, petiolate, the upper side of the leaf surface is dark green and the underside of the leaf is light green. Large, irregularly shaped flowers with a double perianth are arranged verticillately with 2-6 pieces in racemose inflorescences of 5.5-10 inches long. Calyx and corolla are mainly bright red, but they also can be white, purple and pink. It blooms from June until the autumn frosts.
The cultivar of white Salvia splendens differs from bright red salvia by not so dense inflorescence, and by the fact that calyx looks creamy against the background of white corolla.
Pink salvia is characterized by a shorter inflorescence than the red salvia has, calyx and corolla are pink colored, but corolla has a velvety texture.
Purple tropical salvia is a very showy species since dark-violet color of flowers intensifies their velvety that is created by a dense downiness.
The most popular varieties of scarlet salvia are Firestar, Red Arrows, Salvator, Sahara.
Blood sage (Salvia coccinea)
is 20-27.5 inches tall. The stems are straight, densely pubescent and branched. The leaves are petiolate, ovate, serrulate, bottom-pubescent, the upper side of the leaf surface is glabrous. Loose inflorescences are 6-12 inches long, composed of whorled flowers with scarlet-red rim and a long tube. This salvia blooms from July until frost. The varieties are Lady in Red that is up to 16 inches tall with bright red flowers; Cherry Blossom is an early variety of the same height, but with pink flowers.
Mealy sage (Salvia farinacea)
is a long-flowering undemanding plant that is 24-35 inches tall, looking like a pyramidal shrub. The leaves are petiolate, ovate-oblong, with pubescent veins, entire. Inflorescences on high stalks reach a length of 6-8 inches and consist of 5-28 flowers that are up to 0.8 inch. Corolla is usually dark blue, but sometimes it can be white. This species blooms from mid-August until late autumn. The varieties are Anshuld (silver-white flowers), Strata (compact shrub with blue flowers), Victoria (magnificently flowering variety with dark blue flowers).
The second group consists of species of Mediterranean origin. They are hardy to cold and drought-resistant. They are best to grow on loose soils and gratefully respond to mineral fertilizers.
Annual clary, orval (Salvia viridis)
is the species that has only one variety used in ornamental horticulture and it is salvia horminum with brightly colored bracts. It is an annual plant with a height of 15-24 inches, with numerous direct branching stems covered with glandular fluff. The leaves are petiolate, oblong-elliptic, downy. Simple inflorescences are 7-12 inches long, made up of false whorls of 4-6 flowers with pink corolla, but what attracts attention is the color of bracts: it is deep purple or bright pink. The varieties are White Swan (white salvia with pinkish or purple bracts), Oxford Blue with blue-purple bracts, Pink Sunday with pink bracts.
Whorled clary (Salvia verticillata)
is 14-16 inches tall with straight or ascending densely downy stems. The leaves are downy, long petiolate, of unusual shape. The flowers are with dense whorls of 5-30 pieces and with a lilac-blue corolla. The variety Purple Rain has flowers with dark purple corolla and purple calyx.
Dandelion leaved sage (Salvia taraxacifolia)
is a herbaceous species with basal rosette of leaves. The stems are erect, weakly branched, all parts of the plant give off a pleasant aroma. The leaves are pinnatisect, irregularly serrated on the edges, bottom-pubescent, the upper side of the leaf surface is glabrous. Simple inflorescences are up to 11 inches long, made up of whorls with several flowers with pale pink corolla, the throat is green with purple specks.
Salvia jurisicii also belongs to the second group, but it is not of interest to gardeners.
The third group includes cold-resistant species that mostly grow in the temperate zone of the Old World, but Mediterranean sage also belongs to this group. Species of the third group are characterized by abundant flowering in the second year of life. They are undemanding, grow well in the shade and require only shelter in snowless winters.
or Balkan clary (Salvia nemorosa = Salvia sylvestris) is a shrub up to 24 inches tall with branching downy stems. Lower petiolate leaves are larger than upper sessile leaves. Inflorescence with several pairs of lateral branches consist of false whorls of 2-6 small flowers in each. Corolla is blue-purple. Large purple bracts are very showy. It flowers from late June to early autumn. The varieties are violet-blue Mainacht, dark lavender Plumosa, pink-purple Amethyst.
Sticky sage (Salvia glutinosa),
grows well in our climate zone. This is a large plant up to 35 inches high with numerous straight glandular-pubescent stems, large long petiolate ovate-triangular serrated leaves of yellowish-green hue. Flowers in whorls consist of loose inflorescences, corolla is light yellow. It blooms from late summer until late autumn.
Salvia hybrid (Salvia x superba)
is 24 inches in height. It blooms for a long time. Spike-like inflorescences are blue-purple. The varieties are white salvia Snow Hill, dwarf salvia Blue Queen and Rose Queen respectively lavender-blue and pink.
The third group also includes meadow salvia (Salvia pratensis) and the already mentioned Mediterranean sage (Salvia aethiopis).