Botany for Artists


  1. Natural forms have universal appeal because we are adapted to live in nature. Botanical art varies in style and degree of realism, but is no longer “botanical” art if it strays from faithful depiction of the natural character of plants.
  2. Botanical artists, therefore, will be most successful when working from living materials with knowledge of natural growth and development, understanding of comparative morphologies between various plants, and appreciation for the impact of cellular biology on color, texture, and form.
  3. Details of surface and attachment are best learned through drawing, which generates direct connection from hand to brain.

The fruits of botanical art are not limited to scientific studies and documentation. Plant-based figures provide major inspiration for graphics and decorative arts that play into all aspects of our aesthetic lives. Years ago I offered a tour to classes in textile design from the Otis-Parsons School of Design, because I had learned that a large segment of the fabric market is referred toas“florals.”  My goal for those students was similar to thoughts for botanical artists – designs will come across as organic in direct proportion to how attentive the artist is to natural form and patterns. What I learned, of course, was that a repeated “floral” design is about texture and color, and in the textile industry floral patterns can include designs I would call snowflakes or paisley.

Botanical accuracy is not the driving force for fabrics.

Botanical artists, on the other hand, strive for plant renditions that are both beautiful and botanically honest. In the process, their own lives and interests change as the need for realistic portrayal forces observation and engagement. This is because when you draw and paint from nature, you reveal details of plant architecture and form that supersede any other capacity to explain or express that structure – art speaks where words fail us.

But it goes beyond expression and communication. When you draw a complex object, personal learning takes place that is impossible through other means. I contend that people who study and draw objects internalize (learn) and can depict important salient features that are mysteries to others. There is something about drawing that is powerful, constructing a much deeper mental image than can be had through observation alone – I call it hand-eye learning.

It all fits together. Artists who strive to capture the essence of a plant through direct observation and depiction will come to appreciate the perfection of natural forms and gain unique insights that allow creation of both realistic and abstract imagery with inherently beautiful, natural organic rhythm and integrity.

When speaking to a class of artists, my main goal is for students to appreciate the predictable, orderly, and iterative ways plants grow – the fact that plant show structure and architecture which follow a plan. Like individual people, a plant has its own particular set of instructions, but it isn’t lock-step, of course. There is a lot of individuality. Each plant, even each leaf and branch, varies a bit from the next, growing in response to events and local conditions. But a Begonia will always be distinguishable from a Rose, just as a human will not be mistaken for a tiger.

Seeing is believing, so a good place to begin is with a plant stem (or two) in hand. At this point, it is hardly critical which plants we select. Because most botanical artists begin with depicting stems, leaves, flowers, and fruit, similar lessons can be gained from any of many choices. Let’s compare a small Oak branch (a foot or two long with leaves) to a similar-sized Pine branch. These trees are neither closely related nor very similar at first glance, but they both tell familiar stories.

Each branch represents what Botanists call primary (1º) growth – which means you are examining growth formed through the activity of a single growing tip. In both specimens you most likely will have growth from the current season as well as the previous year (or several). Before we determine whether the stem represents one year, versus two or three (or more), it will be good to tie down some hard facts.

Basics: The branch you are examining is made of only two elements: stem or leaf. This means any structure that is not pure stem is going to be leaf tissue.  With the Oak, the stem is highly visible. If actively growing, the stem itself is probably green, but it quickly matures as a brown or tan (or reddish) twig that is marked with corky flecks called lenticels. For the moment, let’s assume you have a leafy stem that has completed its seasonal growth (which happens by early summer here in California.) That means you are holding a fairly rigid stem with a cluster of terminal buds, and several mature, green leaves.

In the life of a plant, the only time leaves are produced is during primary growth, when branches are elongating. Once the leaves you are examining are shed, that stem will not form new leaves – the growing tip or a side bud will have to produce an entirely new branch with leaves. This is both straightforward and confounding, a mystery I realized only recently, while describing the leafless winter stem of English Oak (which is one of the deciduous oaks) for a class. It took a bit of back and forth for me to appreciate that students were puzzled about the naked branch-like when and how would that branch produce next year’s leaves.

It finally dawned on me that I had left the entire audience totally behind, and needed to step back to explain that leaves are only formed by newly elongating branches. Once a branch has formed (with whatever leaves it produced), that stem will never again make leaves. People may be under the impression a branch can make more leaves because lateral buds grow out from existing branches, and those new stems can form their own leaf crop. But leaves are a one-shot deal – they are only produced by primary growth. Each season, to produce a new crop of leaves, a tree has to grow new stems.  A stem may be so short as not to be apparent, but only growing tips make leaves, so there must be new stem tissuepresent.

Let’s focus for a moment on the green leaves. An Oak leaf has a blade and some style of petiole (the stalk by which it is attached to the stem). Each kind of oak has a characteristic leaf shape, a form botanists define by its simplest outline. Lay a leaf down with the petiole closer and the leaf tip further from you. Trace the outer shape (disregarding the petiole and any indentations) for several different leaves. You will be able to apply a term like ovate, or elliptical, or lanceolate to the overall outline that was generated. The reason we placed the leaf petiole at the bottom of our drawing is that botanists always think from bottom to top, …or base to tip, …or close to far, so the shape is defined with thatorientation.

Ovate means “egg-shaped.” Leaves with a rounded outline similar to an egg standing on its broader base would be described as ovate. Lanceolate means lance-shaped, so a long flat (strap-shaped) leaf with an outline that tapers to a tip would be described as lanceolate. Some of the most useful terms to describe simple shapes – cuneate, ovate, lanceolate, oblong, and elliptic – can be augmented as comparatively broad or narrow, i.e. broadly-ovate or narrowly-elliptic. Some kinds of leaves are inverse, being broader at the tip than base. Botanists are unperturbed by this, simply adding the prefix “ob-” to almost any word in order to tell us the shape is inverse. A leaf or petal might be “obovate” – which would tell you it has an egg-shape, but like an egg standing on its narrow end. You can “ob-” almost anything: oblanceolate, obcuneate, obtrullate….

Simple shape excludes so much detail that shape alone cannot define most leaves. For example, they will have interesting details that relate to the base and the tip. This is heart and soul stuff for botanists, and should be for artists also. I look at those evocative Medieval paintings of paradise gardens and know the artists paid no attention to the leaves (or even the branching structure). From image to image, all of the leaves are simple and elliptical – each with a cuneate base (wedge- shaped) and an acute tip.  The only clue as to the kind of tree is usually the color and size of flower orfruit.

Leaf bases are not standard from one kind of plant to another; they are particular, sometimes even diagnostic in identifying plants. Leaf bases can be deeply and roundly lobed, turning a broadly-ovate shape into something that is heart shaped – which we would term cordate (like the leaf of a Redbud). Or the base can be squared-off, truncate, like many kinds of Populus. Each type of plant has its own form.

The same is true for leaf tips. Many leaves have a simple “acute” tip, but some (like the drip-tips of tropical trees) are long and stretched out, a shape we call acuminate. A leaf tip can even be indented, a condition denoted as emarginate. The leaf of Bauhinia is broadly-ovate and basally cordate – which makes it sound similar to that of a Redbud. BUT, it is deeply emarginate, even “cleft”, at the tip – making every Bauhinia leaf appear bi-lobed. A botanist can describe the shape in words and numbers, while only a botanical illustration can give that shape definition far beyond the capacity of terminology.

And other indentations are really significant. Various oaks have lobed or incised leaves – something not taken into account by shape. Hortus describes White Oak leaves as “obovate…. with 5-9 entire, obtuse lobes” – words that will make sense to a taxonomist while giving no single clue to the uninitiated as to what is meant. And take note of the word “entire” because it refers to the last point botanists make about a leaf outline – a description of any peculiarity along the leaf margin. Entire tells us there will be a clean line; we should not find a serrated or crenate edge.

That does not mean we are finished describing the leaf. The upper surface of a leaf typically differs in both color and texture from the lower. Even there we have trouble. Hortus describes whiter color you should expect “beneath” the leaf, but botanists typically stay away from terms like top and bottom, upper and lower. We prefer something a bit more absolute, considering the “top” as the adaxial surface (closest to the stem) and the “bottom” as the abaxial surface (formed away from the stem axis). It doesn’t give me heartache if you refer to the top and bottom of a leaf, just know that in some leaves “top” may not be so easy to discern from“bottom”.

Regardless, the important issue for the artists is that there is often considerable difference in both color and texture between leaf surfaces, and a taxonomist will want your drawing to show both….

We have spent these few paragraphs discussing the “leaf” of our Oak, but the number of normal green leaves on the twig is dwarfed by the many more bud scales, and to a botanist, each scale that covers a bud is also a leaf. If you are drawing an Oak, you have your hands full detailing all the scale leaves because there are buds everywhere – oaks are famous for them. In fact, field botanists rely on the cluster of terminal buds as the primary clue a plant may be an oak.

Examining the entire stem (in the summer), the green leaves are simple (not compound like a Walnut or Jacaranda), and there is only one leaf at a node (unlike Jacaranda, Buckeye, and others). Nestled against the stem, in the angle where the leaf petiole attaches is a lateral bud. Like its compatriots at the stem tip, this bud is covered with scale leaves, but its future is less certain. Most of these lateral buds (especially those closer to the base of the stem) will remain dormant – only springing into action if the stem is cut or damaged in some way. Others will grow actively in the next season.

A field botanist will bother to examine more precisely how leaves are arranged along the stem. We say they fall into ranks – yielding a pattern of production that allows you to predict where a leaf will form around the stem. Oaks, for example, typically have a 5-ranked arrangement, which means there are basically five positions at which a growing tip will produce leaves sequentially. In an oak stem that produces several leaves in a season, you will observe the leaves (or leaf scars in older stems) assuming repeating positions as they spiral down the stem, dictating that each sequence of five leaves aligns with the set before. That means your drawing will only be as convincing as your attention to this repeated pattern.

In oaks, the pattern ends each year with that cluster of terminal buds. They are so tightly crammed together that it is a bit difficult to decipher an arrangement, but it is evident the terminal bud is the strongest – and this is the bud that will take off next year to make the leading branch. Terminal bud growth is not all that happens each season; one to several of the side buds in the terminal cluster (and perhaps some from lateral buds near the tip) are going to grow out also.

This gives oaks their characteristic growth pattern – each year’s twig growth ends with a long, single stem with clustered terminal buds. In the following season the terminal bud will once again extend the main stem while side branches will emerge from other buds that were in or just below the terminal cluster.

But at the beginning of that new growing season (before leaves emerge), oaks flower from buds formed at the end of the previous growth cycle. The stem elongation cycle follows quickly afterward, with growth ending less than two months later. By summer, the new crop of leaves (born on new stems) will have matured and are at their photosynthetic peak.

Active growth is fast and furious, yielding a new long segment of unbranched main stem bearing a cluster of side branches at its base. This yields a characteristic architecture, a starburst- stretch pattern.

The way to examine that pattern is to visually dissect a branch, starting at the tip and tracing structure back to the end of the previous year’s growth. With oaks that is easily determined, because last year’s terminal bud cluster left scale scars on the surface of the twig, and emerging from that ring of scars there likely will be one or more side branches that grew from the cluster. Examining a large branch, it is sometimes possible to identify several successive seasons of growth before the pattern is obscured by secondary growth. If your illustration doesn’t impress the viewer with this replicated pattern, it will be unnatural, andunconvincing.

So how does this compare to the Pine? Oddly, the growth pattern of pines is remarkably similar to that of oaks. Each season begins with a strong leader emerging from clustered buds that will create a whorled arrangement of side branches. 

Study pine branches in the same way as the oak. Your understanding of the pine growth pattern will increase by an order of magnitude. Something that was a blur in the landscape, a mystery, will immediately make sense in the most astonishing and deeply satisfying manner. Every tree, every plant in the landscape will come into focus and make sense as you begin to ask and answer simple questions about its leaf arrangement and particular seasonal growth patterns.

And you do not need a botanist or guide to make this leap. Your eyes can do it, but as an artist, manipulating specimens and drawing what you observe will cement an indelible and intelligible multidimensional understanding of the architecture.

I believe you will be amused by the similarity in growth pattern between oaks and pines (most trees grow a bit more evenly). But otherwise, pines differ greatly from oaks. They are conifers, while oaks are flowering plants. Because pines are resinous conifers, the internal anatomy of stems is readily distinguished from that of oaks. And, of course, the leaves and surfaces are not at all similar. If you decide to paint a pine, spend time in close examination. Texturally, there are three very different kinds of leaves doing three very different things.

Most obvious are the green leaves, the needles. You might guess each needle is round in cross-section (and some kinds of needles are), but most pine needles are more faceted. Roll a needle between your fingers; compress the needles that constitute a single cluster (a fascicle) so they fit back together. Every needle has a shape that complements the other, such that they almost seem to form fitted segments. And each needle is striated, that is, it has fine grooves that run the entire length. There may even be some color variation that runs with those grooves.

Of course a giveaway for pines is that very arrangement of needles in fascicles. This too is predictable, in that most pines consistently produce the same number of needles in each fascicle. White Pines all have five needles per cluster, while Japanese Black Pine has two. Southern Longleaf Pines have three needles in a fascicle, while one of the western Pinyon Pines (Pinus monophylla) bears a single needle. Some kinds of pines have a variable number; Aleppo most commonly produces two, but will have occasional bundles with three needles.

But what is a fascicle? That is actually straight forward. Pine needles are produced from closely spaced, dwarfed lateral buds, which means each fascicle is really a short stem that produces its contingent of leaves (needles) and nothing more. It is like you took a twig with several leaves and sucked the stem down to zero – all that remains is enough stem to have made the leaves and held them together. We see similar behavior in many manifestations throughout the plant kingdom. More closely related to pines, the spruces and deodars create stubby side branches that make clusters of needles. Ginkgo does a similar trick. And way over in the flowering plants, this growth pattern defines cacti, in which areoles (spine clusters) are side branches that produce only leaves (spines).

It is, actually, even more widespread than this. Whole plants will form rosettes (cabbage, lettuce, parsley, agave) or bulbs (onions, tulips) that produce numerous spirally-arranged leaves through broadening the stem without significantly increasing stem length. Of course those plants have a completely different strategy [see Chapter 5; Section 3 – Strategies & Reproduction: An Annual by Any Other Name]; someday the stem tip will bolt – shooting up quickly in order to flower and fruit.

There is a lot of comprehension to be gained from making comparisons between plants, so get used to comparing the plants you paint. Botanists call this comparative morphology, and it is the foundation from which we make sense of “productions of nature.” Like transformers, the hundreds of thousands of forms we find in plants boil down to some rules and mechanisms. Discovering the rules behind each plant will inform your selection, arrangement, and depiction.

OK – Back to the pine. Since the green leaves (needles) are on a short stem, and that stem emerged from a lateral bud, then we have come to expect there were bud scales encasing th yet-to-emerge leaves. At maturity, those scales have stretched out, and now appear as the brown papery leaves that sheathe the base of each fascicle. If you detach a leaf cluster, the fascicle you now hold showcases two different kinds of leaves – the needles and the sheathing scales.

But another set of leaves brings a practically unseen (in fact, ignored) but remarkably significant character to pine stems. Examine a young stem up close. Each branch is completely plated and scaly, like a pattern from some kind of lizard. This texture is wholly different from stem surfaces of flowering trees like oaks. The plates are leaves, called cataphylls. Most botanists simply group them with the fascicular scales, but they look and behave very differently. The cataphylls blanket young stems in a geometrically-definable pattern. Because they are basically leaves, you should not be surprised to learn that each scale corresponds to a node, and may be associated with one of the modest buds that will grow to become a needle fascicle.  Examine the attachment of fascicles (remember these are short branches). Each one sits atop a cataphyll, and when shed it leaves a scar.

For most pines in North American landscapes, young stems bristle with the tips of these cataphylls, but the white pines and their relatives shed their scaly tips, leaving branches considerably smoother.

If pines and oaks have growth patterns that are so distinctive from those of other plants, why concentrate on them? To me the answer is straightforward. You can learn basic structure with any plant, and use that solid understanding as a base from which to make sense of other plants with very different patterns. I selected oak and pine because they are common in all areas of the US, and are likely familiar enough. Most people could fairly confidently identify an oak, with its acorns, and a pine, with its distinctive needles andcones.

I hope that taking the time to discover the wonder baked into a plant so familiar will cause you to look more closely at the world you inhabit, and most particularly at any plant you intend to depict. A specimen in which you plan to invest quantities of time, patience, energy, skill, and artistry merits some stanzas of “getting to know you.”

%d bloggers like this: