Predicting what a plant will do once it’s in the ground is like predicting which horse will win a race. You can look at past results, look at its hooves, check if he likes hot or cool days… but in the end you can never be sure. Plants are the same, and the whole process is complicated by constant new introductions of plants, all supposedly bulletproof. Some are, others not, others become invasive weeds.
Remember that plants can't read. So they don't know that they're supposed to thrive (or not) in your garden.
Of all the aspects of landscape design, plants are the least predictable, since a plant's success depends on all of these things: health of the plant when purchased (diseases...), condition of the plant at purchase (root bound...), care of the plant after purchase, planting time of day, planting season, maintenance after planting, long term maintenance, soil type, irrigation scheduling, normal climate, climate variability (heat, frosts), plant species and variety, nursery location (coastal or inland).
Here in Mediterranean climate California, the best time to plant is in Fall, before the winter solstice, for native and Mediterranean plants in the Sacramento area. Anything tropical should wait until after the soil warms in Spring.
The catch is that plant availability tends to be greatest in spring when people generally buy plants. Some nurseries will let you order plants for fall delivery.
The start and end of the best planting time varies each year, and isn't always predictable. In 2009, hot dry conditions in fall meant that the ideal planting time was later than normal.
This is also an area with a bit of controversy. Some say that larger boxed trees are out of balance with respect to root/crown development and will therefore develop more slowly than a smaller tree.
Our experience has been that after five years, there is still a difference between a 15 gallon and 24" box tree, the boxed tree being larger.
For huge, specimen trees you're basically getting a mature tree instantly. These trees can be expensive when the cost of the tree, shipping and planting are considered. They are also not always in the best shape and are more likely to die than container stock. They may need a lot of additional care for an extended period after planting.
For grasses, we like to specify liners. These are tiny, 2" pots that don't cost much. Grasses grow very quickly, so in a couple of years at the most you won't be able to tell what size pots they came from.
Most plants are available in 1 gallon and 5 gallon pots. If money is an issue, you can plant in one gallon (#1) pots and wait a bit more.
These lawns, which also can be called meadows, replace traditional turf grasses with native sedges to conserve water and reduce maintenance.
There is a bit of controversy as to which species of sedge is best. If you plant a sedge lawn, be aware that you are embarking on an experiment and might need to mix species or otherwise follow the planting closely to make sure it's working.
The current candidates seem to be California Field Sedge / Clustered Field Sege (Carex praegracilis). Other candidates are Carex pansa and European Gray Sedge (Carex divulsa).
To make things more complicated, the non-native European Gray Sege was being sold as Berkeley Sedge (C. tumulicola), and since sedges are very similar, is probably still being sold under the tumulicola name. So, despite its name, the plant generally being sold as Berkeley Sedge is not native to California. It's from Central Europe, but due to a mistake in identification, it was believed to be native tumulicola sedge. It grows very well here, however.
From what we've seen, Carex praegracilis seems to look best in the Sacramento area in heavy soils. Carex divulsa also is doing well, although it gets a bit taller than the praegracilis.
These plants can be mowed occasionally for a neater look. They cannot, however, take the same amount of traffic as a traditional turf grass lawn - but they're good places to sit occasionally and can be walked on.
These don’t always live up to their name as far as hummingbirds are concerned (they tend to prefer native honeysuckle). The plants grow in sun or shade, looking rather peaked in summer if watering is cut back. They’ll pop back to their lush state with winter rains.
This thrives dry areas in full sun and attracts hummingbirds as well as big black carpenter bees.
A low mounding plant covered with flowers for months. The flowers can be white, magenta or a combination of the two colors, depending on temperature. Needs cutting back in spring, otherwise carefree.
Most will die in our cold, wet winters, but some will thrive given good drainage. If you don't want a huge, spiny monster, plant A. parryi. Plant A. vilmorreana for something a bit larger, of if monster is your goal, use A. salmiana.
A trailing daisy that reseeds freely but requires little care. It's not hard to rip out if it's growing where it's not wanted.
We grow upright forms like 'Spice Islands' for cooking. 'Tuscan Blue' is a great bloomer, and the flavor's not bad, either. On mounds.
Their performance has been variable. They’re worth a try, since they’re a nice looking gras that doesn't spread and stays fairly low. Needs to be cut back hard, and may die out in places or look uneven.
A bold, medium-large grass for a native accent. As long as it's in full sun it should thrive.
This is a great seasonal vertical accent. Cut it down completely at the end of winter. Seems to like more regular water than the deer grass, and eventually dies out in the center. Dividing and replanting on a three year cycle should manage the dead centers - but you’ll end up with a lot of grasses!
Part shade, sun, little to moderate water. This plant just doesn't seem to mind variable conditions. Its upright spiky blue-gray leaves stay compact and it doesn't spread.
Pinched back, it makes a nice lacy gray ground cover about 18" high. Our native artemisia, A. douglasii is our locally native species - grow it at the back of the garden where it can ramble, since although I like the smell, it's a bit untidy.
A tree or shrub, the source of bay leaves. Evergreen, dense and a good screen plant. And we never have to buy bay leaves.
Low, neat, evergreen. Happier in part shade with a lot of moisture, it's the main plant in our meadow/rain garden.
California poppies, Farewell to Spring, others. These are in a non-irrigated area. They did very well the first year, and the poppies are consistent performers. The Farewll to Spring and poppies come back, but other species have been variable performers. Plant seed in fall before the first rains, do not irrigate outside of the normal rainy season.
Native to Chile and Argentina, with supposedly edible berries, although we haven't tried them yet. Nice yellow-orange flowers in spring, evergreen. Does not transplant, alas, so it’s only a memory.
A low, somewhat prickly subshrub with yellow flowers in spring, if it feels like it. Better in part shade, it does not need a lot of water to be happy.