Leisure and Cultural Services Department

Planting Herbs in School Scheme

2016/17

Stevia Stevia rebaudiana

Sage Salvia officinalis

Basil Ocimum basilicum

1 [D9-3]PHSS 2016-17 香草(E).ppt

Stevia

Scientific Name: Stevia rebaudiana

Common Names: Stevia, Sweetleaf

Family: Asteraceae

Genus: Stevia

Place of Origin: South America

Distribution: Now widely grown in countries like

Kenya, China, the United States, Vietnam

and India.

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Characteristics

• A perennial herb

• A short-day plant that produces

little white flowers in autumn and

winter.

• Its leaves have a sweet taste and

contain steviol glycosides.

• Steviol glycosides occur naturally

in the plant. They are 200 to 300

times sweeter than sucrose, low in

calories and heat-stable.

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Growth Habits and Care

• Stevia prefers a warm and sunny environment and can

thrive in full or partial sun.

• It should be placed in a cool, shady and well-ventilated spot

on sizzling summer days.

• When the temperature falls below 7°‍C, the plant should be

kept warm.

• It grows well in moist, acidic, sandy soil and performs best

in well-drained, loose and moist humus or sandy soil.

• Water moderately and avoid waterlogging to prevent

infestation and infection.

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Propagation

• The plant propagates mainly by

cutting.

• Propagation can be carried out

when the weather becomes

warmer in spring.

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Prevention and Treatment of

Pests and Diseases • Stevia rarely suffers from pests.

• It requires moist soil that is not waterlogged.

• If it is grown in soil that is over-watered or too wet,

the roots may rot or be attacked by fungus, causing

the plant to wilt.

• Keep the environment clean and

well-ventilated.

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Horticultural Application and

Economic Value

• Stevia is suitable for planting in courtyards and herb gardens.

• If grown as a houseplant, it should be placed in a sunny spot.

• The leaves have a sweet taste and can be used to produce

sweeteners.

• Stevia is used in the commercial production of snacks,

desserts, chewing gum, soft drinks, soybean sauce, table-top

sweeteners, etc.

• While the acceptable daily intake for sugar will not be

exceeded if food containing steviol glycosides is taken in

moderation, individuals (including those taking prescription

drugs) should seek medical advice if in doubt.

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Points to Note

• Regular pinching in spring and summer can promote

branching.

• Pruning should be avoided in winter as the plant grows slower

in cold weather.

• Harvest the plant before flowering.

• After harvesting, apply nitrogen fertiliser as appropriate.

Heavy application of nitrogen fertiliser will make the leaves

less sweet.

• Hang the cut-off parts of the plant upside down

to dry in a warm and airy place. The shorter the

drying time, the sweeter the leaves will be.

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Sage

Scientific Name: Salvia officinalis

Common Name: Sage

Family: Lamiaceae

Genus: Salvia

Place of Origin: Mediterranean region

Distribution: It is now grown worldwide in the southern

part of Europe, the Middle East, Africa and

the United States, while species of the best

qualities mainly come from the United

Kingdom.

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Characteristics

• A perennial herb which also

comes in shrub varieties

• Common varieties include

White Sage, Purple Sage and

Fruit Sage.

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Growth Habits and Care

• Sage prefers a warm, sunny and well-ventilated

environment.

• It is cold-resistant, and must be kept away from

excessive heat and humidity.

• It should be planted in cool and shady areas in

summer.

• It grows best in well-drained sandy soil, preferably

alkaline.

• Appropriate watering is required as excessive

moisture in the soil may cause the roots to rot.

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Propagation

• The plant propagates

mainly by cutting.

• Propagation can be carried

out in spring or autumn.

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Prevention and Treatment of

Pests and Diseases

• Sage is resistant to pests and

diseases.

• If pests or diseases are found,

remove the infected parts and

apply appropriate insecticide or

fungicide immediately.

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Horticultural Application and

Economic Value With its stems, leaves and flowers bearing a unique,

strong fragrance, the plant has a wide range of uses:

• Horticulture - suitable for herb gardens, courtyard

and rooftop planting (when grown in

homes, keep it in a sunny place)

• Culinary use - cooking seafood and poultry,

making tea and food

seasonings

• External use - beauty care, making of

medicine and essential oils

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Points to Note

• Keep the growing media well-drained.

• Place the plant in cool and shady areas in summer.

• As the leaves at the bases of the stems tend to rot

while in contact with the soil, a preventive measure is

to surface the latter with stones and cobbles.

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Basil

Scientific Name: Ocimum basilicum

Common Names: Thai Basil, Asian Basil, Sweet Basil

Family: Lamiaceae

Genus: Ocimum

Place of Origin: Tropical areas and Africa

Distribution: Central-‍southern and

south-‍eastern parts of

China

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Characteristics

• An annual or perennial herb

• Common varieties include Lemon Basil, Purple

Ruffles Basil, Sweet Basil and Purple Basil.

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Growth Habits and Care

• The plant prefers a warm, well-drained environment

with full sunlight.

• It grows best in soil with organic matter and a pH

between 5 and 8.5.

• It is heat tolerant and therefore grows well in Hong

Kong all year round.

• Being highly cold-sensitive, it stops growing

in winter.

• Regular pruning can induce the growth of

lateral buds and improve ventilation.

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Propagation

• Seed sowing can be carried out in spring.

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Prevention and Treatment of

Pests and Diseases • Watch out for attacks from aphids and powdery

mildew.

• The plant is susceptible to powdery mildew if light

penetration or ventilation is poor.

• If pests or diseases are found, remove the infected

parts and apply appropriate insecticide or fungicide

immediately.

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Horticultural Application and

Economic Value

• Horticulture - suitable for planting in herb gardens or

on rooftops (when grown in homes,

keep it in a sunny place)

• Medicinal use

• Culinary use - as an ingredient or sauce

• External use - beauty enhancement

and production of

essential oils

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Points to Note

• Keep the environment well-ventilated during summer.

• Harvest before flowering.

• Apply additional fertiliser, especially nitrogen, after

harvest.

• Keep some flowers in the plant for

seed collection from the fruits.

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Information leaflets on the three herbs and the

relevant presentation materials will be uploaded to

the following webpage in due course:

http://www.lcsd.gov.hk/en/green/education/greeningschool/plant.html

甜葉菊 Stevia rebaudiana

鼠尾草 Salvia officinalis

羅勒 Ocimum basilicum

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