Botanical Name — Euphorbia japonica
Common Name — Pineapple Euphorbia or Cocklebur
Plant Family — Euphorbiaceae
Euphorbia japonica is a dwarf succulent hybrid bred in nurseries from two plants native to South Africa. It’s comprised of lightly-leaved branches growing from a central caudex, or bulbous root system. This slow grower likes a lot of water in the summer and very little in the winter. As the top of the plant grows, the caudex beneath it becomes a hardened brown stalk.
- Euphorbia japonica does best in full sun, at least 5 to 8 hours a day. Avoid intense afternoon sun. Grow outdoors in light shade or indoors in a sunny window with southern exposure and direct sun.
- Euphorbia japonica prefers warm temperatures in the 70s and 80s. It can become stressed if left in conditions of extreme temperatures or intense sun.
- These plants are relatively cold hardy for Euphorbias, but only if they are kept super dry. For best results, bring this plant inside as soon as night time temperatures dip below 50 ºF.
- Thanks to their large caudex Euphorbia japonica are drought tolerant plants. However, for best results in summer months, water fairly often. Don’t let the soil totally dry out. When you do water, the soil should be vaguely moist but not wet.
- Water sparingly throughout the winter. Their soil should be allowed to dry out entirely before watering thoroughly.
- These plants prefer a sandy, sharply draining mix. Cacti or succulent potting mix is great. You can amend a regular potting soil with sand or pumice up to 50% to improve grittiness and drainage.
- These plants produce small yellow-green flowers during the spring and summer time. Potted plants and plants grown indoors may not flower.
- These plants do not require fertilizer though it can be added to give container grown plants a boost or to supplement poor soil. Apply a water-soluble, balanced fertilizer monthly, diluted at half strength.
- Euphorbia japonica can be propagated from stem cuttings. Take great care when cutting these plants as they contain a sap that can be highly irritant if contacted with skin.
- Allow cuttings to callous for several days before dusting with rooting hormone and placing in soil.
- Euphorbia japonica are not prone to pests. Though not super common, they are more likely to fall victim to bacterial or fungal infections. Affected plants may need to be destroyed to prevent the spread of disease to other nearby plants.
- Root rot can also be a concern and is triggered by overwatering. Always err on the side of underwatering.
Maintenance (pruning, legginess, repotting)
- Little maintenance is required to grow these plants.
- The deep, bulbous roots of this plant often require a deep pot, but once planted, they will be happy in the same pot for several years. Repot once every two to three years.
- All Euphorbia plants contain a poisonous sap that is very toxic if ingested and highly irritant if contacted with skin. Keep out of reach of pets and children. Wear gloves and take great care when handling this plant.