Cacti & Succulents Garden

Air plants (Tillandsia) for interior decoration have been popular for a while. They are evergreen, perennial flowering plants, which are native to Central and South America, the southern US. There are around 650 species, which naturally grow in diverse environment, from forests to deserts, from coasts to mountains. The name "air plant" comes from their capability to grow without soil. Most are epiphytes, which attach to other plants. However, they do not steal nutrients or water from their host, only using it as a home to grow on. And some are aerophytes, which have no roots and grow on shifting desert dirt. Most species absorb moisture and nutrients through the leaves from rain, dew, dust, decaying leaves and insects. Air plants photosynthesize through a process called CAM cycle, where they close their stomata during the day to prevent water loss and open them at night to fix carbon dioxide and release oxygen. This allows them to preserve water, because they can ...

Soil is a mixture of minerals, organic matter, gases, liquids, and organisms that together support life. If you have watched the movie "the Martian" (2015), you may remember Matt Damon used Martial dirt (minerals)  fertilized with human waste, which contains bacteria, and water to grow potatoes on Mars. Let's look at the components to have better idea of soil. Typical Soil Profile 1. Minerals Minerals include sand (size > 63 µm), silt (size > 2 µm) and clay (size < 2 µm). Generally, sand helps to drain water, and clay helps to retain water. The ratio of them will determine the soil texture. You may have heard "loam soil". Loan has sand-silt-clay of  40–40–20% by weight. Loam is considered ideal for gardening and agricultural uses because it retains nutrients well and retains water while still allowing excess water to drain away. And typical loam soil constitutes: Water (25%), Gases (25%), Sand (18%), Silt (18%), Clay (9%), Organic mat...

Pests are the No.2 enemy to cacti & succulents lovers, following overwatering (mentioned in another post https://succulents-minwei.blogspot.com/2017/09/planting-and-caring-cacti-succulents.html). Moorten Botanical Garden_Palm Springs CA The most common ones in bay area are slugs (also snails) and mealy bugs. 1. Slugs & Snails Slugs and snails like to stay in damp shady area. They feed on leaves and fleshy stems. They attack not only succulents, but also cacti in some occasions. They leave ugly holes and tell-tale slimy traces. Below are two examples. The best solution is to move the plants to sunny area and reduce watering frequency. If possible, don't place the pots directly on soil. I have posted a DIY project to make plant pot shelves (https://succulents-minwei.blogspot.com/2017/09/diy-plant-shelf-from-pallets.html). During moving, check the bottom of the pots to remove the slugs & snails. Also check the backside of leaves. The problem should go ...

It is often assumed that cacti and succulents need little care because they come from deserts. It is true in some sense, since they can tolerate a great deal of neglect. However, they are likely retreat into dormancy and look unattractive. Therefore, it is important to treat them fairly as other plants. The key factors are: soil, light, water, temperature, and nutrients. Soil --- growing medium Well-drained soil is important. They may rot from the roots up in poorly-drained soil. I use nursery mix, which is an all purpose soil mix for outdoor use. It is quite sandy, containing Top Soil, Garden Compost and Fine Redwood Amendment. Avoid heavy clay soil which drains poorly. Most cacti and succulents like a slightly acid soil (pH 5.5 ~ 6.5). Light Most cacti and succulents are best cultivated outdoors  with full sun (at least partial sun) in warm climate. However, if they are in small pots, full sun in summer might be too much for them ---- move them to a partial sun spot....