Heat Wave in SF Spurs Captive Mamaki Growth - CCAG Will Invest in Heater to Sustain It's Growth

The heat wave last week has helped our one of our Hawaii Endemic mamaki plants, which were mere sprouts a month ago, grow an absurd 3 inches of growth,

Planted June 22, 2026 the mamaki plants had a rough start. The plants used to grow outside in the hot greenhouse but when the sprouts reached a certain age they would always end up scorched by the heat lamp or succumb to root rot.

As the plants can tolerate more mild temperatures, I brought some tiny sprouts inside the house which was around 65ºF. I tracked a singular plant's growth. A couple months after the plant date, San Francisco had several small heat waves, with three or more days in a row peaking at 80ºF or higher. Only a few weeks after I moved the sprouts from the greenhouse inside, the mamaki started to spring back. On August 2 (roughly 6 weeks after planting), one plant was around 3 inches tall with very strong mature leaves. In addition, the red veins signify the plant's steady growth in the more mild temperatures.

Low quality photo of the biggest Mamaki plant taken August 2, 2026 in my room where the plants are stationed

Mamaki is a short lived perennial. It is in the nettle family so it grows in a similar habit as the weedy relatives. However in optimal conditions the plant can grow to the size of a small woody shrub or tree and live for more than 10 years.

In that pot with the large Mamaki there is another sprout, but it still has it's cotyledons and it's growth is stunted. The larger mamaki is likely stealing it's nutrients but I will leave it in the pot to see if it comes back.

In a different pot, there are some younger plants that were planted August 2026. These are still sprouts and there are around 5 of them.

All the mamaki will be transplanted after we implement the heating plan (see below) and the plants have reached 2 or 3 feet

Proposed solution to Hawaiian Greenhouse Heating Problem

To increase it's lifespan, we are investing in a heating system for the greenhouse.

The greenhouse's temperatures tend to fluctuate based on outside temperatures. This means when a heat wave occurs, the greenhouse becomes hot, stuffy and dry and when there is a rainstorm, it becomes soggy and cold.

The new heating system will mimic the daily highs and lows of a real tropical ecosystem - a high temperature of around 80ºF and a low nighttime temperature of around 60ºF. During intense heat waves the heating system will turn off until the threshold is below a certain temperature.

In addition we hope to install a humidifier system which will provide a solution to the constant dryness and encourage the growth of moss.

The project will hopefully be complete by January 2027 - including both heaters and humidifier system.