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Botanical Illustration 3: Advanced Techniques

Learn botanical illustration online

Advanced Techniques is one of nine online courses we offer in our Horticulture Distance Learning Program.


To build on previous experience with botanical drawing techniques by using various art media, culminating in the development of a portfolio. The course offers the opportunity to explore media such as art markers, pastel, charcoal, colored pencil, tempera and gouache, and to mix media to capture the essence of your botanical subjects. The portfolio assignment provides the opportunity to reflect on one’s work, explore new directions, and prepare a portfolio for presentation to employers, galleries, or schools. 

Learner Outcomes

Upon completion of this course, you will be able to:

  • Observe nature through both a scientific (structural) and an artistic (aesthetic) lens at an advanced and detailed level.
  • Articulate a personal aesthetic -- what appeals to you, and what you enjoy.
  • Demonstrate proficiency with different media including pencil, ink, chalk, colored pencil, and pastels.

Course at a Glance

Welcome and an Introduction: Course Overview

Lesson 1: Review of Elements and Principles

  • Exercise 1.1: Lines, Patterns and Shading with Pencil Techniques Assignment
  • Exercise 1.2: Composition with Pen and Ink Assignment
  • Exercise 1.3: Revisiting the Color Circle Assignment
  • Exercise 1.4: Portfolio Development Assignment
  • Optional Exercise: Adobe Photoshop

Lesson 2: Technical Drawing with Pen and Ink

  • Exercise 2.1: Roots with Pen Techniques Assignment
  • Exercise 2.2: Flower Parts with Quill and Ink Assignment
  • Colored Pen Techniques file
  • Exercise 2.3: Colored Pen Illustration Assignment
  • Exercise 2.3b: Colored Pen Illustration Assignment

Lesson 3: Textures and Dimensions Found in Nature; geometric forms; charcoal and chalk

  • Exercise 3.1: Drawing Geometric Forms with Pencil Assignment
  • Exercise 3.2: Overlay and Shadowing Assignment
  • Exercise 3.3: Charcoal and Chalk Illustration Assignment
  • Charcoal Techniques Part One file
  • Charcoal Techniques Part Two file
  • Exercise 3.3b: Charcoal and Chalk Illustration Assignment

Lesson 4: Watercolor and Colored Pencil, Mixed Media

  • Exercise 4.1: Watercolor Assignment
  • Exercise 4.2: Colored Pencil Techniques Assignment
  • Exercise 4.3: Colored Pencil Illustration: Iris sp. Assignment
  • Blending with Colored Pencils file
  • Exercise 4.4: Mixed Media Illustration Assignment
  • Exercise 4.5: Portfolio Development Assignment

Lesson 5: Identification and Portrayal of Plant Characteristics

  • Exercise 5.1: Pencil: Pleurotus ostreatus Assignment
  • Exercise 5.2: Pen and Ink: Quercus spp. Assignment
  • Exercise 5.3: Colored Pencil: Rosa spp. Assignment

Lesson 6: Final Lesson – Illustration and Portfolio Review

  • Warm Up 6.1: Preparing for your Final Illustration Assignment
  • Final Illustration Assignment
  • Portfolio Review Assignment


  • Instructors: Sonja Williams sw955 [at] (sw955[at]cornell[dot]edu)
  • Note: You will not be able to access the online course website after the course ends.

This 6-lesson course builds on previous experience, and helps the student to go further in technical proficiency. You will gain considerable experience with botanical drawing techniques by using various art media, culminating in the development of a portfolio. There is an expectation that students will engage deeply in study, making a commitment to gaining expertise and producing a portfolio that demonstrates the range of your ability. Our approach will be to introduce you to a range of media and exercises, with the anticipation that you will genuinely delve into each.

    Course Basics

    This course teaches a traditional form of botanical illustration, along with a few different creative exercises. We will employ a more scientific approach, which is an advantage for plant identification and description. This is essential to becoming a botanical illustrator.

    This course promotes illustration to experience the plant world in a scientific and creative way in order to express ourselves during the process. Although you can become as proficient as you wish, the course instruction will focus on the basics in a supportive environment of selfdiscovery.

    This is a course that you are likely taking for your own personal enrichment and proficiency. As such, I hope that you are intrinsically motivated to complete readings and all assignments, including optional assignments, to devote considerable time to drawing, and to communicate with your colleagues freely and often in an effort to get the most from this course. I will assign readings, and I will assume you read them; I will not "test" you on content because I do not believe that should be your motivation. You will get from the course what you put into it.

    Our communication will be positive and will focus on course content. Rude or offensive language, and overly critical commentary will not be tolerated. It is a course taken for enrichment, and the way we communicate with one another will be constructive.

    Please be open with your feedback and feel free to contact us with any questions. Open dialogue is encouraged.

    With this in mind, we ask that you begin without demanding expectations of your artistic abilities for each lesson or upon completion of the course. Keep an open mind, and please remember that it can take a lifetime of illustration to develop the kind of skill that you see in the text! A seed takes a long time to grow into a plant, flower, and fruit. Our development as artists is similar.

    Learning to illustrate is like learning to play the piano: you would never expect yourself to be playing symphonies at the end of your first lesson, and yet often, it seems the people have this expectation with art techniques. Please take the time to enjoy yourself and get lost in the process, particularly since it offers the additional benefits of providing an experience that gives you a break from the rush and bustle of daily life.

    The text we have chosen will provide you with a reference for the terms and techniques introduced, while providing you with supplemental exercises that will help you to sharpen your skills on your own. Your illustrations will not likely be as well developed as the author's and it would be unwise to have that expectation from the course onset. Use the exercises for inspiration.

    It is important that you choose a comfortable, quiet place to practice drawing and complete your assignments. All of the numerous, everyday distractions can disrupt creative flow, limit your focus, and hinder a careful understanding of the plant material you will choose as your subject. So, shut off the cell phone and enjoy the break in the action!

    We recommend that you set up your art supplies in a place where they can be readily accessed, rather than have to bring them out each time you use them. This will encourage you to practice more. If you don't have a place where you can leave your supplies uninterrupted, keep them close at hand, in a box underneath your desk or table to eliminate the chore of searching for supplies when you feel inspired.

    Course Work

    You will need to have some access to plant materials for drawing: houseplants, gardens, stems from the grocery store or florist, produce, collected leaves or twigs, etc. They need not be expensive, and can be very simple, but it is critical that you work from life. There will be times when working with a photograph or other image is tempting, appropriate, or perhaps necessary. For the requirements of this course, however, unless we ask you to use an image or a photograph for the photo, please work from the 'real thing.' If that is impossible, please work from your own photographic images.

    You may find some of the lessons to be very straightforward in their approach. Although you need to submit the basic requirements each week, you certainly may embellish and add to them if you wish.

    In the course you will create up to six finalized works of art that will become part of your portfolio. At the end of the course I will review those portfolios. You are expected to either create a hand or digital portfolio. As you advance your artistic skills, you will want to have an organized collection of your work. In the first lesson we will go over what is expected of your portfolios, along with tools and tips for portfolio development. 

    Your reflective writing will allow you to develop new observational skills as well as a dialogue with the course instructor and your peers. Reflection is something that you can do at home, at work, or during a stroll through the garden. It is a very important part of developing the creative and observational components of your brain, something we expect to improve not just your drawing ability, but your full range of activities around creativity and the plant world. It will encourage you to make connections between the course and your life experience, in addition to reflecting on course content.

    One of our favorite books: Botanical Illustration Course with the Eden Project by Rosie Martin and Meriel Thurstan

    We will assign readings from this book, so it is required that you purchase it. The book can be found online or at a library.

    Optional Reading

    A list of optional books to be used with this course can be found in the 'Additional Resources' topic at the end of the course. To access the list, simply click the Materials for Further Exploration resource.

    These books can be found in your local bookstore or library. If you have trouble finding them, try online book vendors.

    Graphite pencils. These drawing pencils can be purchased at any craft store or local art supplier. I suggest purchasing wood-encased graphite pencils that require sharpening, rather than buying mechanical pencils that can carry leads of different hardness for reasons that will be clarified when we learn line and shading techniques.

    Drawing pencils come in several degrees of hardness which will produce lines of varying darkness. The softest pencil is the 6B, which will produce the darkest line. the hardest is 6H, providing a finer, sharper line. Between these is a continuum of hardness from the hardest to the softest: 6H 5H 4H 3H 2H HB 2B 3B 4B 5B 6B

    You can buy a set of pencils that will contain all or a selection of these, or you can purchase them individually. If purchasing individually, make sure to span the hardness range with your selections. Another excellent drawing pencil is the Sanford Ebony Jet Black pencil #14420.

    Erasers. You will need two of these. A Kneaded eraser is made of pliable gum rubber; when kneaded, it will resemble a large, chewed piece of gum. This can be pulled to a point to reach inside small spaces for erasure. A Plastic eraser or White Vinyl eraser is somewhat flexible and excellent for cleanly erasing larger parts of a drawing.

    Sharpener. A good sharpener produces a long, sharp tip. You may consider sharpening your pencils with a craft knife since it will allow the pencil to last longer.

    Drawing Paper. Drawing paper is available in different weights and sizes. For the different range of mediums: pencil, ink, pastels, and charcoal you should purchase the appropriate paper for the type of art medium. You will want to try different papers to experiment to find out which you prefer, and should start out with inexpensive papers. The paper is available in sheet form, or in blocks.

    Set of Black Pens. Purchasing a good set of black pens with a wide range of sizes is important for this course. 'Micron' or 'Prismacolor' pens are great for illustrating because of the lasting quality of Pigma ink. These pens are acid-free and archival. Unlike dye-based ink found in most pens and markers, Pigma ink will not feather or bleed, even through the thinnest paper. Pigma ink is derived from a single pigment to ensure color consistency, and is fadeproof against sunlight or UV light. Pigma inks will not clog or dry out like most mechanical pens.

    Speedball Crow Quill Dip Pen with Nibs and Ink. This is the more traditional option for ink (instead of micron-type pens). Please select your pens of choice.

    Colored Marker Set. Designed for detailed work, Prismacolor Premier Double-Ended Art Markers (or similar high quality brand) feature an advanced dye-based alcohol ink formulation that ensures rich color saturation and coverage, and smooth, silky ink flow. These markers can be purchased as individual markers, or in sets. [Note: if you are working with a budget constraint and materials are a concern, I am glad to talk with you about substituting additional watercolors for your colored marker assignments! I know that materials can quickly add up.]

    Charcoal, chalk, tortillions, and fixative. Charcoal is available in natural sticks of willow and vine charcoal, and compressed charcoal in various grades in stick or pencil form. Carbon pencils are a blend of charcoal and graphite with an oilier binder which gives a soft feel. Compressed charcoal and pencils vary in texture according to the blend of charcoal, clay and fillers used in their manufacture. Ideally, purchase a small selection to try, as preference is a matter of personal taste. You should also purchase a small set of tortillions (used for blending), white chalk and fixative spray.

    Watercolor. Most students will have taken the course Working with Watercolor; many students have requested the opportunity to go further with their watercolor. You will need tube paints of transparent watercolor (not opaque, and not acrylic or other paint); palette; brushes; watercolor paper.

    Colored Pencil Sets. For creating successful botanical illustrations with colored pencil, not any type of colored pencil can be used. Prismacolor colored pencils are great for blending color and creating a smooth surface. These pencils can get expensive, so start out with a small set. Sometimes online art stores have great sales on this item. There are several other excellent brands, such as Faber-Castell Polychromos, Derwent, and Caran D’Ache.