Rosemary Cone Trees: Care for Your Holiday Tree

By Richard Flowers, ACCNP-Green Thumb Nursery-Ventura

A rosemary cone tree is a living upright rosemary plant (Salvia rosmarinus) pruned over a cone frame into the shape of a small Christmas tree. It is real, edible culinary rosemary, not a cut conifer, so you care for it like a potted herb that needs full sun and excellent drainage, and it can live on long after the holidays.

Rosemary cone tree care at a glance

Question	Answer
What is a rosemary cone tree?	It is a living upright rosemary plant pruned into the shape of a small Christmas tree.
Is it real rosemary you can eat?	Yes, it is the same culinary rosemary, but only cook with it if the grower confirms it was not treated with pesticides that are unsafe for food.
How much light does it need?	Rosemary grows best in full sun, so give it the brightest window or a sunny outdoor spot.
How often should I water it?	Water only when the top inch of soil is dry, because overwatering is the leading cause of rosemary decline.
Indoors or outdoors?	In mild Southern California winters it can stay outdoors, since rosemary is hardy in roughly USDA zones 8 to 10.
How do I keep the cone shape?	Trim it lightly and pinch the tips so growth stays tight and compact.

What Is a Rosemary Cone Tree?

A rosemary cone tree is not a special plant but a familiar herb trained into a festive shape. University of Wisconsin-Madison Extension notes that rosemary (Salvia rosmarinus, the plant long known as Rosmarinus officinalis) is a member of the mint family that can be grown as a topiary.^[1] A grower prunes and shears an upright rosemary over a cone-shaped form until it resembles a miniature evergreen, so the little Christmas tree on your table is actually a living culinary herb, the very same rosemary you would cook with. The Missouri Botanical Garden describes rosemary as a generally erect evergreen shrub that reaches about 4 to 6 feet tall where it is winter hardy, and that naturally upright habit is what makes a tall, narrow cone possible.^[2] Because it is a real, growing plant rather than a cut conifer, a rosemary cone tree can keep going well past December if you treat it like the herb it is.

How to Care for a Rosemary Cone Tree

The two things rosemary wants most are strong light and sharp drainage. On light, the answer to the common question is clear: rosemary grows best in full sun. Penn State Extension lists full sun as its requirement, and the Missouri Botanical Garden notes rosemary tolerates light shade but performs best in full sun.^[3] Indoors, that means the brightest window you have, usually a south-facing one. For a deeper look at growing and using the herb, see our guide to growing rosemary.

On water, less is usually more. University of Wisconsin-Madison Extension is blunt that the biggest cause of rosemary decline and death is overwatering, and that good drainage is a requirement.^[1] At the same time, a potted plant should not be allowed to dry out completely; University of Illinois Extension notes rosemary dries out quickly in an indoor environment, which browns the tips.^[4] The balance is simple in practice:

• Water only when the top inch of the soil feels dry to the touch, then water thoroughly and let the excess drain away.
• Use a pot with drainage holes, and never leave the plant standing in a saucer of water.
• Give it the brightest spot available, and turn the pot now and then so the cone grows evenly on all sides.
• Trim lightly and pinch back the tips to keep the cone tight and compact.

Keeping It Alive Indoors Through the Holidays

Most holiday rosemary trees are lost indoors, not outdoors, and the reasons are predictable. Penn State Extension points out that overwintering rosemary indoors can be difficult because of low light and because of too little or too much water.^[3] Those stresses show up as disease: University of Wisconsin-Madison Extension reports that root rot and botrytis are the most common disease problems, and that good air circulation is important to prevent foliar disease such as powdery mildew.^[1] To carry a rosemary cone tree through the holidays, set it in your brightest window, keep air moving around it rather than tucking it into a crowded corner, and err on the side of slightly dry rather than soggy. If you also keep a living conifer, our guide to potted living Christmas trees covers similar indoor care.

Cooking With It, Pet Safety, and Life After the Holidays

One of the nicest things about a rosemary cone tree is that it is genuinely useful. Good news for pet owners first: the ASPCA lists rosemary as non-toxic to dogs, cats, and horses, using the scientific name Rosmarinus officinalis on its plant-safety page.^[5] On the kitchen side, rosemary is a true culinary herb, but there is one important caution for an ornamental plant. The University of California statewide program explains that a pesticide may legally be used on an edible plant only if that use appears on the product label, and that many landscape and home products are not cleared for food use at all.^[6] A plant sold as decor may have been treated with something not meant for food, so only cook with your rosemary if the label or the grower confirms it was not treated with anything unsafe to eat. After the holidays, plant it in a sunny, well-drained spot or keep it as a potted herb, and it will keep producing. For more ideas, see our guides to culinary herb gardens and holiday herbs and how to grow them.

Looking for a living holiday gift that keeps giving? Stop by any Green Thumb Nursery and our team can help you choose a rosemary cone tree and the right pot, light, and care to keep it thriving well into the new year.

Rosemary Cone Tree FAQ

What is a rosemary cone tree?

It is a living upright rosemary plant pruned over a cone-shaped form into the shape of a small Christmas tree. University of Wisconsin-Madison Extension notes rosemary can be grown as a topiary, so the tree is real culinary rosemary, not a cut conifer.^[1]

Does rosemary like full sun?

Yes. Rosemary grows best in full sun. Penn State Extension lists full sun as its requirement, and the Missouri Botanical Garden notes it tolerates light shade but performs best in full sun, so give a potted cone tree the brightest spot you have.^[3]

How do you care for a rosemary cone tree indoors?

Put it in your brightest window, keep air circulating around it, and water only when the top inch of soil is dry. University of Wisconsin-Madison Extension warns that overwatering is the biggest cause of rosemary decline, so avoid soggy soil while not letting the plant dry out completely.^[1]

Can you eat rosemary from a cone tree?

It is the same edible culinary rosemary, but an ornamental plant may have been treated with pesticides not cleared for food. University of California guidance notes pesticides are legal on edibles only when the label allows it, so only cook with it if the grower confirms it was not treated with anything unsafe to eat.^[6]

How do you keep a holiday rosemary tree alive?

Give it full sun or the brightest window, good air circulation, and careful watering, then move it outdoors in mild Southern California winters, where rosemary is hardy in roughly USDA zones 8 to 10. University of Illinois Extension notes potted rosemary dries out quickly indoors, so check the soil often.^[4]

Sources

• [1] University of Wisconsin-Madison Extension, Rosemary (Salvia rosmarinus): hort.extension.wisc.edu
• [2] Missouri Botanical Garden, Plant Finder: Salvia rosmarinus: missouribotanicalgarden.org
• [3] Penn State Extension, Herb Garden Plants: Rosemary: extension.psu.edu
• [4] University of Illinois Extension, Rosemary: extension.illinois.edu
• [5] ASPCA, Toxic and Non-Toxic Plants: Rosemary: aspca.org
• [6] University of California (UC ANR, UC IPM), Applying Pesticides around Edible Gardens: ucanr.edu

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