master the garden

part five botany basics: buds
photo -l.fowler

Plant buds are undeveloped or embryonic shoots that arise on the tip of a stem or in the axil of a leaf. Composed of meristem tissue and containing undifferentiated cells, from which different plant structures develop and grow, and fueled by the rapid cell division when conditions are right they are formed in late summer/early fall and remain small and delicate and in most temperate-zone trees and shrubs. In these cooler climates the buds are covered with tough protective scales, formed by modified leaves, that enables them to remain dormant during the winter, whereas, annual and herbaceous perennials have naked buds with green fleshy outer leaves and are very tender. The buds of many plants require a resting or inactive state and exposure to a certain number of days below a critical temperature before they resume growth in the spring.

Forsythia, a deciduous flowering shrub in the Family Oleaceae, requires a relatively short period of rest and grows at the first sign of warm weather, usually early spring. The bloom proceeds the leaves.

photo – Forsythia x intermedia wikipedia

classifications: buds and can be classified in two ways, according to their location on the plant or according to the immature structures within the buds.

A leaf bud is composed of a short stem with embryonic leaves and is vegetative. (Those that contain only immature leaves are called leaf buds, while those buds containing both flowers and leaves in the earliest stages of development are termed mixed buds).

photo – Sycamore wikimedia commons

Flower buds are also composed of a short stem but contain embryonic flower parts and are reproductive. Flower buds on herbaceous plants and on woody plants are made up of undeveloped and tightly packed groups of cells that are the precursors of the various floral parts—petals, stamens, and pistils—with a whorl of sepals or outer leaf bracts covering and protecting the inner parts of the flower bud. Flower buds are sometimes referred to as fruit buds because they can develop into fruit, but only if the right circumstances occur such as pollination, or favorable weather conditions.

By B.traeger – Own work, CC BY-SA 3.0,

location: buds are named for their location on the stem

terminal buds: A terminal bud is located at the apix, or end on a woody twig. It overwinters and grows out during the next spring and summer into a new shoot that extends the length of the twig and may also produce flowers. Some examples of this type of growth are found in apple and cherry blossoms.

photo – black ash,

lateral or axillary buds: These buds are located on the sides of a stem, usually where the leaf meets the stem, or axil, and depending on the cells that developed inside the bud during the previous fall, growth from the lateral bud will produce a branch or a leaf. .

photo – Corylus avellana Wikimedia Commons

adventitious buds: in botany the word adventitious mean something that grows where it would not normally, so in the case of buds, this grow occurs away from the apical meristem in such places as shoots, internodes, edge of a leaf blade, callus tissue, or roots – which can result in a whole new plant. They connect with the phloem and xylem for nourishment, and it is one way that a plant can reproduce asexually. They can grow at anypoint in a plants life and can also facilitate growth if the apical meristem is damaged or removed.

photo –

buds as food

The enlarged parts or buds from some horticultural crops are edible. Cabbage and lettuce heads are usually terminal buds and brussel sprouts are axillary buds. With the globe artichoke, the solid stem, fleshy basal portion and the flower bracts are consumed.

top left – Gurney’s seeds top right – Seeds for Generations, bottom left – l.fowler, bottom right – Farm Flavor

glossary of terms

Anther – The pollen sac on a male flower

Apex – The tip of a root or shoot

Apical dominance – The tendency of an apical bud to produce hormones that suppress growth of buds below it on the stem

Apical meristem – the growth region in plants found within the root tips and the tips of the new shoots and leaves. Apical meristem is one of three types of meristem, or tissue which can differentiate into different cell types. Meristem is the tissue in which growth occurs in plants.

Axil – The location where leaf joins the stem

Basal plate – bottom of bulb from which roots develop

Bulb – is structurally a short stem with fleshy leaves or leaf bases that function as food storage organs during dormancy

Bolting – plants produce a flowering stem in a natural attempt to produce seeds as a means of survival when under stress.

Cambium – A layer of growing tissue that separates the xylem and phloem and continuously produces new xylem and phloem cells

Chlorophyll – The green pigment in leaves that is responsible for trapping light energy from the sun

Chloroplast – A specialized component of certain cells; contains chlorophyll and is responsible for photosynthesis

Cold hardy – generally measured by the lowest temperature a plant can withstand

Cortex – Cells that make up the primary tissue of the root and stem

Cotyledon – The first leaf that appears on a seedling. also called a seed leaf.

Corms – bulbo-tuber, or bulbotuber is a short, vertical, swollen underground plant stem that serves as a storage organ that some plants use to survive winter or other adverse conditions such as summer drought and heat

Cuticle – A relatively impermeable surface layer on the epidermis of leaves and fruit

Dermal tissue – covers the outer surface of herbaceous plants. It is composed of epidermal cells, closely packed cells that secrete a waxy cuticle that aids in the prevention of water loss

Dicot – having two seed leaves

Herbaceous – vascular plants that have no persistent woody stems above ground

Epidermis – The outermost layer of plant cells

Fibrous roots – a network of feeding lateral roots found on most plants

Ground meristem – an area of primary meristematic tissue, emerging from and immediately behind the apical meristem, that develops into the pith and the cortex

Guard cell – Epidermal cells that open and close to let water, oxygen and carbon dioxide pass through the stomata

Internode – the space between nodes on a stem

Lateral root – roots that branch from larger primary roots

lenticel: small, oval, rounded spots upon the stem or branch of a plant that allow the exchange of gases with the surrounding atmosphere

Marginal meristems – the meristem located along the margin of a leaf primordium and forming the leaf blade. The apical meristem or growing tip, is a completely undifferentiated meristematic tissue found in the buds and growing tips of roots in plants.

Meristem – Specialized groups of cells that are a plant’s growing points.

Meristematic zone – located at the tip of a root and manufactures cells: it is an area of cell division and growth

Mesophyll – A leafs inner tissue, located between the upper and lower epidermis; contains chloroplasts and other specialized cellular parts (organelles)

Monocot – having one seed leaf

Mycorrhizae – symbiotic association between certain fungi and roots of a plant

Node – an area on a stem where a leaf, stem, or flower bud is located

Ovary – The part of a female flower where the eggs are locate

Periderm – the outer layer of plant tissue: the outer bark

Petiole – The stalk that attached a leaf to the stem

Phloem – Photosynthate-conducting tissue

Pistil – The female flower part; consists of a stigma, style, and ovary

Pith – or medulla, is a tissue in the stems of vascular plantsPith is composed of soft, spongy parenchyma cells, which store and transport nutrients throughout the plant. … In trees pith is generally present in young growth, but in the trunk and older branches the pith often gets replaced – in great part – by xylem

Primary root – originating at the lower end of a seedlings embryo and continues to elongate downward. It may or may not persist into plant maturity, and has limited branching – it is called a tap root

Procambium –  is a meristematic tissue concerned with providing the primary tissues of the vascular system; the cambium proper is the continuous cylinder of meristematic cells responsible for producing the new vascular tissues in mature stems and roots

Protoderm – The primary meristem in vascular plants that gives rise to epidermis. Also called dermatogen

Respiration – the process of converting sugars and starches to energy

Rhizomes – is a modified subterranean plant stem that sends out roots and shoots from its nodes. Rhizomes are also called creeping rootstalks or just rootstalks. Rhizomes develop from axillary buds and grow horizontally. The rhizome also retains the ability to allow new shoots to grow upwards

Root cap – group of cells protecting the apical meristem at the root tip

Root hairs – delicate, elongated epidermal cells that occur in a zone behind the root’s growing tip with the function of increasing the roots surface area and absorptive capacity

Root plate – That part of the root system (excluding the small outermost roots) needed to keep a tree wind-firm.

Stamen – The male flower part; consists of an anther and a supporting filament

Stigma – The top f a female flower part; collects pollen

Stoma (pl. stomates, stomata) – tiny openings in the epidermis that allow water, oxygen, and carbon dioxide to pass into and out of a plant

Suberin – a waxy material found in bark that can repel water

Style – The part of a female flower that connects the stigma to the ovary. Pollen travels down the style to reach the ovary, where fertilization occurs

Tap root – see Primary root

Transpiration – the process of losing water (in the form of vapor) through stomata

Tuber – enlarged structures in some plant species used as storage organs for nutrients. They are used for the plant’s perennation, to provide energy and nutrients for regrowth during the next growing season, and as a means of asexual reproduction. Stem tubers form thickened rhizomes or stolons

Tunic – skin-like covering that protects the fleshy scales

Turgor – Cellular water pressure; responsible for keeping cells firm

Vascular tissue – Water, nutrient, and photsynthate-conducting tissue (xylem and phloem)

Vegetative structures – The vegetative (somatic) structures of vascular plants include two major organ systems: (1) a shoot system, composed of stems and leaves, and (2) a root system

Xylem – Water and nutrient-conducting tissue

Zone of elongation – located behind the meristem. Cells in this area increase in size through food and water absorption. As they grow, they push the root through the soil

Zone of maturation – located directly beneath the stem. Cells in this zone become specific tissues such as epidermis, cortex, or vascular

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: