Pencil tree / Milk bush

Pencil tree / Milk bush key facts

Growing Difficulty

Beginner-friendly

Lifespan

Perennial shrub or small tree

Size

5–9 m in the wild (60 cm–1.8 m in pots)

Watering

Light feeder; avoid very rich soil

Light & Placement

Thrives in bright indirect light to full sun; in hot summers some afternoon shade helps.

Watering

A summer grower. Water after the mix dries, about every 1–2 weeks; overwatering causes root rot. Water less in winter.

Temperature & Overwintering

Tropical to subtropical and cold-sensitive; a Japanese reference gives 5°C as its limit, so keep it in a bright room in winter.

Soil & Repotting

Use a free-draining mix; indoors a coarse, loamy mix with grit and not too much organic matter suits it.

Propagation

Propagate from cuttings, wearing gloves and eye protection to avoid the latex, and let the cut dry before inserting.

Pests & Cautions

The latex is extremely irritating and can cause temporary blindness. Keep the plant away from children and pets. Watch for spider mites, aphids and mealybugs.

About Pencil tree / Milk bush

The milk bush (pencil tree) is a perennial euphorbia with coral-like, pencil-thick green branches and no thorns. Beginner-friendly and 60 cm to 1.8 m in a pot. Its sap is strongly toxic, so see our care and handling tips.

7 things to know before growing Pencil tree / Milk bush

1. 1Give it plenty of light

   The milk bush does best in a bright spot. With too little light, the branches grow thin and leggy, and the leaves drop more easily. Indoors, put it in the brightest window you have. When moving it outdoors, get it used to direct sun gradually rather than all at once.

2. 2Water only when dry

   Wait until the soil is completely dry, then water thoroughly until it runs out of the drainage hole. The plant stores water in its fleshy branches, so soil that stays constantly wet can lead to root rot. If you are unsure, it is safer to wait a few more days than to water too soon.

3. 3Choose fast-draining soil

   A succulent and cactus mix, or a soil blended with plenty of akadama or pumice, works well. A mix that does not hold water in the pot helps prevent root problems. Choose a pot with drainage holes.

4. 4Repotting and pruning

   Do both repotting and pruning during the warm growing season. Move the plant to a pot one size larger once the roots fill the current one. As it grows taller it becomes top-heavy, so choose a stable pot and cut back overly long branches to keep the shape balanced. Wear gloves, because cuts release sap.

5. 5Protect it in winter

   The milk bush comes from warm regions and does not like the cold. In winter, bring it into a bright indoor spot and water much less, keeping the soil on the dry side. Leaves may drop and the branches may look a little duller, but the plant can recover as the weather warms up.

6. 6Handling the white sap

   The white sap that flows when a branch is cut or broken is strongly toxic. Wear gloves and eye protection when working on the plant, and keep it out of reach of pets and small children. If sap touches your skin, rinse it off with plenty of water, and seek medical advice if symptoms persist.

7. 7Choosing a healthy plant

   Look for a plant whose branches are firm and glossy green, with no wrinkling, blackening, damage, or stickiness. This species drops its leaves quickly, so a lack of leaves is not a sign of poor health. Also check that the base is stable and that the overall shape is well balanced.

Frequently asked questions about Pencil tree / Milk bush

Q.Can beginners grow it?

A.Yes, it is rated as suitable for beginners. If you keep it in a bright place, water only after the soil dries, and protect it from the cold in winter, it is an easy plant to grow.

Q.Is the white sap dangerous?

A.Yes, the sap is strongly toxic and needs careful handling. Wear gloves and eye protection when cutting or repotting, and keep the plant away from pets and small children. If sap touches you, rinse it off with plenty of water and seek medical advice if symptoms continue.

Q.How big does it get?

A.In its native habitat this perennial shrub or small tree grows 5 to 9 m tall. In a pot it reaches about 60 cm to 1.8 m, and you can trim overly long branches during the growing season to control its size.

Q.Is it dead if it has almost no leaves?

A.Not necessarily. This plant drops its leaves quickly, and its green branches are the main feature. If the branches are firm and green, all is well. Wrinkled, blackened, or soft branches may be a sign of overwatering or cold.

Q.Can I grow it indoors?

A.Yes, it can be grown indoors on a bright windowsill. Too little light makes the branches thin and leggy, so choose the brightest spot you can and keep the air moving around the plant.

Handy Growing Tools for Pencil tree / Milk bush

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