Pachypodium decaryi

Pachypodium decaryi key facts

Growing Difficulty

Advanced

Lifespan

Slow-growing and long-lived (little published data)

Size

Nearly 2 m tall (occasionally 4 m); caudex up to 40 cm across

Watering

Sparingly in the growing season

Light & Placement

Grow in full sun to light shade. It can go outdoors in sun in warm weather, but keep it out of rain.

Watering

Water sparingly in the heat of the growing season and not at all from late autumn to mid-spring. The older the plant, the less water it needs; never leave it damp in cool weather.

Temperature & Overwintering

It is cold-sensitive; overwinter it completely dry at about 16°C at night and 20°C or more by day. It shows some cold resilience when bone dry, but protect it from frost.

Soil & Repotting

Use a gritty, porous mix that is not strongly acidic. Repot about every three years.

Propagation

Mainly propagated from seed; fresh seed germinates well after soaking in warm water for 24 hours.

Pests & Cautions

The sap is toxic, so avoid contact when the plant is damaged. As an Appendix I species, international trade in wild-collected plants is prohibited, so plants on the Japanese market are mainly seed-raised. Even so, check for a registration certificate before buying or listing.

About Pachypodium decaryi

Pachypodium decaryi is a slow-growing Madagascar caudiciform with a rounded grey caudex, spineless branches, and some of the genus's largest pure white flowers. A long-lived species best suited to experienced growers.

7 things to know before growing Pachypodium decaryi

1. 1Light and Airflow

   Give it as much sunlight as possible throughout the year. Good airflow also helps prevent pests and disease, while insufficient light tends to make the branches grow leggy.

2. 2Water Sparingly

   Water sparingly during the hot part of the growing season, and stop watering entirely from late autumn to mid-spring. The older the plant, the less water it needs; never let it stay wet in cool weather. Overwinter it completely dry.

3. 3Well-Draining Soil

   Choose a fast-draining mix formulated for succulents or cacti. Blending in akadama or pumice improves aeration and helps keep the roots healthy.

4. 4When to Repot

   Because growth is slow, repotting is only needed every few years, once the roots begin to feel crowded. Doing it around the start of the warm growing season puts the least stress on the plant.

5. 5Overwintering Care

   It isn't very cold-hardy, so move it to a bright indoor spot once temperatures start to drop. It may drop its leaves during dormancy, but new growth returns once the growing season resumes.

6. 6Choosing a Healthy Plant

   Look for a plant with a firm, plump caudex free of scarring or discoloration. The way the branches grow and the condition of the leaves are also good indicators of overall health.

7. 7Patience Until It Blooms

   Once mature, the plant produces some of the largest pure white flowers in the genus. Since growth is slow, it takes patience to reach that first bloom.

Frequently asked questions about Pachypodium decaryi

Q.Is this a good plant for beginners?

A.Pachypodium decaryi is generally considered a plant for experienced growers. Because watering timing and winter care require some know-how, it's best to try it after you've gained experience with succulents or other caudiciforms.

Q.How large does it eventually grow?

A.It can reach nearly 2 meters in height, occasionally up to 4 meters, with a caudex that can thicken to about 40 cm across, making it a relatively large-growing species.

Q.When and what kind of flowers does it produce?

A.Once the plant matures, it produces pure white flowers up to about 12 cm across, among the largest in the genus. Because growth is slow, it takes patience to see it bloom.

Q.Does it grow quickly?

A.No, it's a slow grower. In exchange, it develops into a large, long-lived plant over many years.

Q.Can it stay outdoors in winter?

A.It isn't very cold-tolerant, so it's best moved to a bright indoor spot once temperatures drop. It may lose some leaves during dormancy, but new growth resumes in the growing season.

Handy Growing Tools for Pachypodium decaryi

Learn more about Pachypodium decaryi in the encyclopedia

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