Main stages in a plant’s life cycle Plant Growth Patterns.

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TYPES OF PLANT GROWTH Main stages in a plant’s life cycle Plant Growth Patterns

Transcript of Main stages in a plant’s life cycle Plant Growth Patterns.

TYPES OF PLANT GROWTH

TYPES OF PLANT GROWTHMain stages in a plants life cyclePlant Growth Patterns

The Life Cycle of a PlantSeeds germinateFoliage stem and root formation

Flower and fruit/seed productionseedsPlant growth PatternsAnnuals- plants complete their life cycle in a single season.Biennials-plants complete their life cycle over two seasons.Perennials- plants live for longer than two seasons.AnnualsCosmos bipinnatus(Mexican aster)

annualsExperience dormancy only as a seed as they dies during autumn or winter.The life of an annual can be prolonged by removing spent flowers(deheading).

Completes life cycle in a single growing season.Life cycle stages of annualsGrow rootsProduce stems and foliageProduce flowersProduce seedsSenescence(death)Seed germinationThe plants we use in our gardens come from all over the world, therefore some plants that are perennials in one climate, such as tropical, are not hardy in our temperate climate. These plants are generally used as annuals in northern climates since they succumb to the cool temperatures of our winters. If their seeds are cold-hardy, they may germinate the next spring, depending on the severity of the winter. However, for practical purposes we treat these plants as if they were annuals.Hardiness designationsAbbreviationName DescriptionATenderAnnualsPlants and seeds are not frost hardy.HHAHalf Hardy AnnualsPlants will tolerate some frost.HAHardy AnnualsPlants may tolerate some frost.Seeds overwinter and self-sow.Winter annualsGerminate in autumn, bloom in late autumn, winter or early spring and die the following summer.Examples:Stellariamedia(chickweed)Lamiumamplexicaule(henbit)Barbareasp.(bittercress)Secalecereal(winter rye)An important pointSow annual seeds directly in the soil(direct sowing) if they are hardy, usually after the frost is no longer predicted. Most tender annuals are better sown indoors as they need warm soil temperatures to germinate and would not have enough time to mature in our climate if sown directly.BiennialsDigitalis purpurea(foxglove)

Biennial plants need all or part of two growing seasons to complete their life cycle as they require a cold period before they will flower. That is why they flower in the second year, not the first.Germination from seed.Root growthFormation of rosetteDormancy over winterFlower productionSeed productionSenescenceLife cycle of Biennials.Biennials germinate from seed, produce foliage then become dormant during the winter. In spring they produce an abundant amount of seeds, then the parent plant usually dies. Biennials are known as profuse seeders and it is these seeds that continue the cycleGenerally, most biennials have very short, compressed stems(crown) with leaves low to the ground forming a rosette. The flowers are usually borne on a long stem that emerges from the centre of the rosette. Biennials are often propagated by seed.Examples of biennialsFoxglove(Digitalis purpurea)Sweet William(Dianthus barbatus)Hollyhock(Alcea bienni)

Biennial veggies:BeetsCarrots ParsleyParsnipsCabbageKaleHerbaceous Perennials Periennial plants live for at least two growing seasons and produce non-woody growth that dies down in autumn as they enter their winter dormancy. In spring they emerge once again sporting new growth. Germination from seed.Root growthFoliage GrowthMay produce flower and seedDormancy over winter

Spring:New foliage , more roots, larger coloniesSeed & Flower productionSenescence after many yearsLife cycle of Herbaceous PerennialsSome dont produce above-ground stems, such as irises, they only produce foliage. Although they dont get taller as the years progress as trees do, their roots multiply forming large colonies. A litle clump of daisies easily becomes a massive grouping, hence the appeal of herbaceous perennials.Examples of herbaceous perennialsChrysanthemum

Hosta

Delphinium

Daylily

Columbine

Monocarpic PlantsMonocarpic Plants(often called monocarps) are usually short-lived as they die after flowering. Almost all annuals and biennials are monocarpic. Some herbaceous perennials also exhibit this same trait such as the Agave americana(Century Plant). It lives for approximately 25 years until it flowers, then it dies. Many bamboo species are also moncarpic.Bedding PlantsBedding plants sold in nurseries are often tender and half hardy annuals as well as biennials and sometimes perennials. They are usually grown through the winter and early spring from seed in greenhouses and are available to the public through the spring and summer.Woody PerennialsTrees and shrubs possess bark on their stems and do not die or wither in the fall. They continue to grow year after year becoming taller and wider until they reach their mature height and width. Woody plants have sturdy stems containing tough, fibrous tissue while herbaceious perennials typically have soft succulent stems.Climbing PlantsThere are two climbing plant categories: herbaceous(vine) and woody(liana). Both grow from the ground and prefer to be supported by an arbor, trellis or even other plants. Lianas are usually associated with tropical forests as they make their way through the tree canopy. They use the surrounding trees as their support as they search for light and space. Not all lianas are tropical plants as the Wisteria and Clematis are temperate plants that grow locally.24Vines can have perennial or annual growth or both depending on the species such as Morning Glory(Ipomoea spp.), Sweet pea(Lathyrus odoratus) is a common garden annual vine as so are numerous vegetable including indeterminate(vining) tomatoes, cucumbers and scarlet runner beans.

Virginia Creeper (Parthenocissus quinquefolia) Climbing plants have many ways to climb up their supports. Some produce tendrils that curl like springs around anything they touch. Other use suction cups or roots tat grow from the stems.Whatever method they use, care must be taken as many vines and lianas are quite aggressive and can crush their supports such as the wisteria. English ivy(Hedera helix) is very successful, invasive liana that will climb trees, eventually smothering them.Classification of Woody and Herbaceous PlantsWOODYTreesTsuga spp.Shrubs

Mock Orange (Philadelphus spp)

Climbers (lianas)Wisteria(Wisteria spp.)HERBACEOUS

Self-supporting(perennials)

Peony(paeonia spp.)

Climbers(vines)Clematis(Clematis spp.)Deciduous or Evergreen? Evergreens deciduousWoody plants that KEEP their foliage throughout the year.Woody plants that LOSE their foliage in the autumn.In temperate zones, deciduous trees typically lose their leaves during the coldest season(winter) but in tropical climates, deciduous plants often lose their leaves during the dry season . Some popular deciduous trees used in landscapes include the maple (Acer spp.), oak(Quercus spp.) and dogwood(Cornus spp.) have broad, flat, blade-like leaves. The shape of the leaf, its method of attachment to the stern and the arrangement of leaves along the stem varies greatly from one species to another.

Maple (Acer spp.)Evergreens

The term Evergreen doesnt mean that a tree of shrub never loses a leaf, its just that they dont do it all at once like deciduous plants. Instead, leaf shedding and replacement is a gradual, on-going process which may take several years. Depending on the genus, evergreens have either broadleaf, needle-like, scale or awl-like foliage.Broadleaf Evergreens

Not all evergreeens have needle-like foliage, some have broad leaves similar to deciduous plants, but they dont lose all their leaves in autumn. Examples are Photinia (Photinia X freseri), Holly (Ilex spp.) and many Rhododendrons(Rhododendron spp.)

Holly (Ilex spp.) Trees like Pine (Pinus spp.), Fir (Abies spp.) and Spruce (Picea spp.) have slender leaves called needles. Needles vary in length from one species to another. They may be sharp, rounded or notched at the tip and either flattened or triangular in a cross section. The needles may be soft or stiff, be in clusters or singly(Pines have needles in bundles of 2 or 3 or 5). The bundles are called fascicles.Needles

Spruce (Picea spp.)Scales and AwlsTrees like western red cedar (Thuja plicata), false cypress (Chamaecyparis spp.) and juniper(Juniperus spp.) have small, flattened, overlapping leaves which resemble scales on a fish. Among the conifers the term scale is often used to decribe the leaves.

juniper(Juniperus spp.) Coniferous EvergreensEvergreens that bear cones are referred to as coniferous, such as the pines (Pinus spp.), cedars (Thuja spp.) and spruce (Picea spp.). However not all conifers are evergreen as some shed their needle-like leaves in autumn such as Larches (Larix spp.) and Dawn redwoods (Metasequoia glyptostroboides).

Coastal Lodgepole Pine (Pinus contorta var. contorta)