Where it grows and what it looks like
Purslane is a hot-weather plant. It will not sprout until the ground temperature is somewhere between 76 and 90 degrees F. A strong hot sun warming the soil along with good moisture are required for it to sprout below 80 degrees.
The sprouts are green with a reddish
tint. The first four leaves look like little rounded propellers surrounding a
reddish engine tip. At first, these early leaves are elliptical, but they get a
little fatter near the tip very quickly. The tips of these leaves are about as
rounded as you can get, not pointed at all.
In general, purslane sprouts and grows best in the hottest four months of the year. Once established, it is very drought resistant. If a young plant is growing in dry conditions, growth will slow and the plant may be tiny. This can be seen often in the cracks of sidewalk cement. The plant starts growing, but the moisture dries up. In these conditions, the plant is so small that it goes unrecognized by most people.
If a healthy more-established plant is exposed to very dry conditions, its stems will pull the moisture from the leaves and drop them. The stems, however, survive longer and can grow new leaves when moisture returns. If conditions continue to dry, even the stems will die.
As long as the days are long, vegetative growth continues. Great growing conditions will hold off flower and seed development for awhile. I've seen individual stems up to eighteen inches long.
Purslane is a succulent, a plant that retains a lot of water in its leaves and stems. Those leaves and stems appear thick and fleshy relative to their size. This ability to store water is what helps this plant thrive in heat and survive drought.