Morning Glory vs Clematis: The #1 Mistake Gardeners Make on Fences

The Vining Dilemma: Choosing Your Perfect Climbing Plant

Every gardener dreams of a trellis or fence draped in stunning, colorful blooms. When it comes to climbing vines, two names immediately spring to mind: Morning Glory and Clematis. Both promise vertical beauty, but choosing the wrong one can lead to years of regret.

The core problem lies in their superficial similarities. Both climb, both flower, and both can transform a barren structure into a living masterpiece. This often leads to an impulse decision at the garden center, a choice that can result in an invasive mess or a disappointing lack of growth.

This guide will finally end the confusion. We will dissect the fundamental differences between these two popular vines, exploring their growth habits, care needs, and long-term impact on your garden. By the end, you will be equipped to make an informed decision that brings you joy, not frustration.

Meet the Contenders: A Tale of Two Vines

Before diving into a direct comparison, it’s essential to understand the individual character of each plant. They may look similar from afar, but they are fundamentally different botanical beings with unique needs and behaviors.

The Eager Morning Glory: A Fleeting, Fierce Beauty

Morning Glory (Ipomoea purpurea or Ipomoea tricolor) is the sprinter of the garden world. It is an **annual vine**, meaning it completes its entire life cycle—from seed to flower to seed—in a single growing season. Its calling card is its trumpet-shaped flower that famously opens in the morning and closes in the afternoon sun.

Known for its incredibly rapid growth, it can cover a trellis or fence in just a few weeks. This vine is often confused with its relative, the night-blooming moon flower, which shares a similar vining habit but opens its fragrant white blossoms after dusk.

The Elegant Clematis: A Perennial Queen

Clematis, on the other hand, is the marathon runner. It is a **herbaceous perennial**, meaning the top growth may die back in winter, but the root system lives on for many years, re-sprouting each spring. Clematis is renowned for its astonishing variety of flower shapes, sizes, and colors.

Unlike the simple trumpet of the morning glory, clematis flowers can be large and star-shaped, small and bell-like, or intricate double blooms. This diversity, combined with its longevity, makes it a true investment in the garden’s structure and future beauty.

Growth and Lifespan: The Sprinter vs. The Survivor

The most critical difference that every gardener must understand is the growth rate and lifespan of these two vines. This single factor will determine how you manage them and how they behave in your garden for years to come.

The Explosive Growth of an Annual

Morning Glory grows with an explosive, almost unstoppable vigor. From a small seed, it can easily reach heights of 10-15 feet in one season. This speed is perfect for quickly covering an unsightly feature or providing temporary summer privacy.

However, this vigor comes with a significant catch: it reseeds prolifically. The seeds that drop in the fall will sprout with abandon the following spring, often turning a beautiful vine into an invasive weed that chokes out neighboring plants. Managing this spread is a primary challenge for anyone who plants it.

The “Sleep, Creep, Leap” of a Perennial

Clematis follows a well-known perennial growth pattern: the first year it “sleeps” (focusing on root growth), the second year it “creeps” (showing modest top growth), and the third year it “leaps” (exploding with vigorous growth and blooms). This requires patience.

Unlike morning glory, clematis is a long-term resident. A well-cared-for clematis can thrive for 50 years or more, becoming a permanent and cherished feature of the landscape. Its growth is focused and manageable, rarely spreading beyond its intended space.

Aesthetic Appeal: The Battle of the Blooms

While growth habit is a practical concern, the visual reward of flowers is often the deciding factor. Both vines are beautiful, but they offer very different aesthetic experiences in the garden.

Flower Form, Color, and Season

Morning glories offer a consistent, charming look with their 2-3 inch trumpet-shaped flowers, primarily in shades of blue, purple, pink, and white. They are classic late-summer bloomers, providing a final burst of color from July until the first frost.

Clematis, however, offers unparalleled diversity. With hundreds of cultivars, you can find flowers from 1 inch to 10 inches across, in nearly every color of the rainbow. By planting different varieties, you can have a succession of blooms from early spring all the way through fall.

Support Structures: Twining vs. Grasping

A little-known difference lies in how they climb, which directly impacts your choice of trellis. Morning glories have twining stems that wrap themselves around anything they can find, making them ideal for poles, strings, or traditional lattice.

Clematis, however, climbs using its leaf stems (petioles). These act like little hands, grasping onto slender supports. They cannot grab thick posts; they need thin wire, netting, or a fine trellis (less than 1/2 inch in diameter) to climb effectively.

Side-by-Side Comparison: The Ultimate Cheat Sheet

To make the choice crystal clear, here is a direct comparison of the most important attributes of Morning Glory and Clematis. This table breaks down the key factors at a glance.

Feature	Morning Glory (Ipomoea)	Clematis
Lifespan	Annual (one season)	Perennial (many years)
Growth Rate	Extremely fast; can reach 15 feet in months	Slow to establish; “Sleep, Creep, Leap” pattern
Sun Needs	Full sun (6+ hours)	“Head in the sun, feet in the shade” (cool roots)
Soil Preference	Tolerates poor soil; less fertilizer is better	Requires rich, well-drained, alkaline soil
Climbing Method	Twines its main stems around supports	Uses leaf petioles to grasp thin supports
Invasiveness	HIGH RISK. Reseeds aggressively and can become a noxious weed.	Low. Generally well-behaved and stays where planted.
Pruning	None needed; remove vine after frost.	Required; varies by 3 distinct pruning groups.
Primary Use	Quick, temporary coverage for one season.	Permanent, long-term vertical garden feature.

Care and Maintenance: Demands and Dangers

Beyond planting, the long-term care requirements for these two vines are worlds apart. One thrives on neglect, while the other demands specific attention to perform its best.

Soil, Sun, and Feeding

Morning Glory is famously easy to please. It thrives in full sun and tolerates average to poor soil. Crucially, do not fertilize your morning glories. Rich soil or added fertilizer will result in lush, green leaves but very few, if any, flowers.

Clematis has a famous mantra: “head in the sun, feet in the shade.” This means the vine itself needs at least 6 hours of sun, but the root zone must be kept cool and moist. This is typically achieved by planting low-growing perennials or placing mulch over the base. It prefers rich, well-drained, and slightly alkaline soil, and benefits from regular feeding during the growing season.

The Pruning Puzzle Solved

Pruning is perhaps the most intimidating aspect of growing clematis, but it’s simple once you know the rules. Clematis are divided into three pruning groups based on when they bloom. Pruning an annual morning glory, however, is not necessary; you simply pull the dead vine down after the first hard frost kills it.

• Group 1: Blooms on old wood in early spring. Prune only right after flowering.
• Group 2: Blooms on both old and new wood. Prune lightly in late winter/early spring to remove dead wood and shape the plant.
• Group 3: Blooms on new wood in summer/fall. Prune hard in late winter, cutting back to about 12 inches from the ground.

Invasiveness: The Unspoken Risk

The single greatest risk of planting morning glory is its potential for aggressive, invasive spreading. The vine produces copious amounts of seeds which can remain viable in the soil for decades. What starts as a single beautiful vine can quickly become a neighborhood-wide problem, choking out other plants and becoming nearly impossible to eradicate.

Clematis, with very few exceptions (like Sweet Autumn Clematis in some regions), is not invasive. It stays put, respecting its boundaries and coexisting peacefully with other plants. This makes it a much safer and more responsible choice for a carefully curated garden.

The impact of an invasive vine can be surprisingly far-reaching. While you’re enjoying the flowers, its dense mat of roots can be depleting soil nutrients, potentially affecting the health of your nearby vegetable patch and leading to problems like unripe zucchini due to resource competition. The level of care required for some plants can vary dramatically; the simple needs of a morning glory stand in stark contrast to the highly specific conditions required for something more exotic, like a successful Nepenthes flowering.

Making the Final Choice: Which Vine Wins Your Space?

The decision between morning glory and clematis ultimately comes down to your goals, your patience, and your tolerance for maintenance. There is a right and a wrong answer for every garden.

Choose Morning Glory if…

• You need to cover something fast and for only one season.
• You are gardening on a budget and want a big impact from a cheap packet of seeds.
• You have a large, isolated area where its aggressive reseeding will not interfere with other plants.
• You understand and are prepared to diligently remove seed pods before they drop to control its spread.

Choose Clematis if…

• You are creating a permanent garden feature and want a plant that will return for decades.
• You desire a huge range of choices in color, flower shape, and bloom time.
• You have a sturdy, permanent trellis and are willing to provide the right soil conditions.
• You prefer a well-behaved plant that will not create a future weed problem.

The Final Word: Can Morning Glory and Clematis Grow Together?

Many gardeners ask if they can plant both vines on the same trellis to get the best of both worlds. The answer is a resounding **no**. This is a recipe for disaster.

The hyper-aggressive morning glory will quickly overwhelm the slow-starting clematis. It will twine around the clematis, blocking its access to sunlight and competing for water and nutrients. In this battle, the clematis will always lose, leading to a weak, smothered plant that will never thrive. Always give these two vines their own separate spaces.