Actual size and flowering may vary slightly based on season.
Aloe petricola
Aloe petricola, often called stone aloe, is a low, stemless South African aloe with a rounded rosette of blue-gray leaves that curve inward. In winter it sends up tall stalks of two-tone flowers, red in bud and opening cream, that draw hummingbirds. It stays about 1.5 to 2 feet tall and 2 to 3 feet wide. Use it in a rock garden, a dry bed planted in a group, or a large patio pot.
Best for: rock gardens and rocky slopes, group plantings in dry beds, hummingbird gardens, and large patio pots.
In the wild it grows among rocks with only shallow soil over the roots. A rock garden, a boulder bed or a sloping bank with fast drainage suits it well.
Planted in a group, it gives a strong winter display of red and cream flower spikes. Set the plants about 3 feet apart, center to center.
The tube-shaped winter flowers draw hummingbirds and other nectar birds, along with bees. Leave the stalks up until the flowers fade.
Soil that stays wet can rot the roots, and hard frost below the mid 20s can damage the leaves. The leaf edges carry sharp brown teeth, so keep it back from walks.
- Group planting3 ft apart
- Open group3-4 ft apart
Give it a few days to a week without water after planting so any damaged roots can heal. After that, water it on a steady schedule until new growth shows it has rooted.
Water about every 2 weeks in spring, summer and fall, letting the soil dry between drinks. Give it less water in winter, especially after rain.
Most aloes look better in a Valley summer with some afternoon or filtered shade. If the leaves turn reddish or purple, it is stressed, so check the water and the sun it gets.
On frosty nights, drape frost cloth or a sheet all the way to the ground, not plastic. Take it off in the morning once it warms.
Cut off dead flower stalks once the winter flowers fade. That is the only pruning it needs.
Drainage test first. Dig the hole and fill it with water. If water is still sitting in the hole a day later, you likely hit caliche, clay or hard soil, so fix the drainage before planting. If it drains very fast, the soil is sandy. Standing water around roots is a common reason new plants fail.
Weed cloth. Cut it away from the planting hole and where the roots will spread. Remove any plastic sheeting completely, since it keeps water and air out of the soil.
Rock or decomposed granite with no soil underneath. Bring in soil close in texture to your native soil, mix it with the soil below, and build up enough depth for roots before planting.
If you can break through. Use a breaker bar, pick, or jackhammer. Dig through the caliche and break out the solid chunks. Backfill with the soil you dug out, with no compost or manure in the hole. Confirm drainage before planting.
If you cannot break through. Dig narrow holes through the hard layer beside the root ball, not under it, and refill them with the same soil, not gravel. If it still will not drain, plant on a low mound of the same soil.
Root ball. Check the outside edges for any roots circling around. Loosen or cut those so they grow outward. Do not break up the center of the root ball.
Depth. The top of the root ball should sit at or just slightly above the surrounding soil level. Planting too deep can lead to rot and kill the plant.
Drip emitters. At planting, put the emitters on the root ball, on different sides of the plant. After about 2 months, move them to the outer edge of the root ball. Over the first year, add emitters farther out toward the edge of the branches as roots grow. Once a plant is rooted, never water only at the trunk.
How big does Aloe petricola get?
It grows about 1.5 to 2 feet tall and 2 to 3 feet wide as a low, stemless rosette. The flower stalks rise well above the leaves, to about 4 feet.
When does Aloe petricola bloom?
Its flowers come in winter. Tall, dense spikes open from red buds to cream or greenish-white flowers, so each spike shows two colors. Cut the stalks off once the flowers fade.
Does it attract hummingbirds?
Yes. The tube-shaped flowers are rich in nectar and draw hummingbirds, plus bees and other birds. A group planted near a window or patio makes them easy to watch.
Does it need full sun or shade?
It grows in full sun to light shade. In the Valley, most aloes look best with some afternoon or filtered shade in summer, so give it a spot out of the hottest western sun.
How often should I water it?
Once it is rooted, water about every 2 weeks in the warm months and let the soil dry between drinks. Water less in winter, and skip it after a good rain.
How cold hardy is it?
Most listings rate it to about 25°F, and South African growers call it fairly frost hardy. On colder nights, cover it with frost cloth or a sheet draped to the ground, not plastic.
Does it make pups?
It mostly grows as a single rosette and can slowly form a small clump over time. If pups appear, cut them off with a clean knife, let the cut dry about a week, then plant them.
How fast does it grow?
It grows at a slow to moderate pace. The 15 gallon size gives you a fuller rosette from the start.
Can I grow it in a pot?
Yes. It stays low and compact, so it works well in a large pot. Use a pot with a drainage hole and a gritty cactus mix.
Are the leaves sharp?
The leaf edges carry sharp brown teeth, and some leaves have small prickles on the faces too. Wear gloves when you work around it and keep it back from walks.
Is Aloe petricola toxic to pets?
Yes. Aloe is toxic to dogs, cats and horses. Chewing it can cause vomiting, diarrhea and lethargy, so plant it where pets will leave it alone.
Aloe petricola for sale in Arizona, delivered to you
Aloe petricola, the stone aloe, grows wild on rocky outcrops in Mpumalanga, South Africa, and its name means growing among rocks. Below is what to expect in a Valley yard, including size, sun, water, cold, winter blooms, hummingbirds and the spots where it fits best.
Sourced from trusted Arizona growers and delivered directly to your door, job site, or property. We deliver across the Valley and to nearby towns, and quote delivery anywhere else in Arizona.
When does Aloe petricola bloom in Arizona?
It blooms in winter, when tall spikes open from red buds to cream flowers. Hummingbirds visit the flowers through the cool months.
How big does Aloe petricola get?
It grows about 1.5 to 2 feet tall and 2 to 3 feet wide. The flower stalks rise to about 4 feet above the low rosette.
Does Aloe petricola need shade in Phoenix?
It grows in full sun to light shade. Like most aloes in the Valley, it looks best with some afternoon or filtered shade in summer.
How cold hardy is Aloe petricola?
Most listings rate it to about 25°F. Cover it with frost cloth or a sheet to the ground on the coldest nights.
How far apart do you plant Aloe petricola?
Plant a group about 3 feet apart, center to center, or 3 to 4 feet apart for a more open look. The Spacing tab on this page counts plants for your bed.
How do you water Aloe petricola?
Water about every 2 weeks in the warm months and let the soil dry between drinks. Give it less water in winter, and make sure the soil drains well.
Aloe petricola vs Blue Elf Aloe
Both are low aloes with blue-gray leaves and winter flowers that hummingbirds visit. Aloe petricola carries two-tone red and cream spikes on a wider, single rosette, while Blue Elf forms tight clumps with orange flowers.
We deliver across the Valley, from Phoenix, Scottsdale and Mesa out to San Tan Valley, Maricopa and Casa Grande, and up to Prescott, Sedona, Payson and Globe. See delivery areas and rates.