Based on San Francisco Bay Area Climate by Mitsuo Umehara

Transplanting and repotting - Transplanting time that started in late February is still applicable.
1. Pine - Transplant your pine as soon as the candle shows movement and until the growth of the candle stops and the needle buds come out like a pimple around the candle. This is about the same time as the Japanese flowering cherry (akebono) blooms which in the Bay Area is mid-March.
2. Deciduous trees - Most deciduous trees can be transplanted after the buds begin to show the GLOW and until they start growing.
3. Old junipers - February or September is the best time for transplanting.
4. Ume (apricot) - Transplant after flowering and until the leaf buds start to move.
5. Crabapple, Chinese quince, akebia - Hold off transplanting until October once the flowering starts. All flowering and fruit/berry bearing trees should have a sprinkle of either bone-meal or Magamp-K (7-40-6) in the bottom of the pot, but on top of the coarse gravel, when transplanting.
6. For more information see Repotting Basics
Pollination
1. Akebia and Karin - Blooms early and requires artificial pollination. For a successful pollination, there should be two or three trees each, of male and female, on hand.
2. Crabapple and bittersweet - Protect the blossoms from rain. Bittersweet will require one male tree for several female trees
3. Proper fall fertilization will determine the flowering success on flowering and fruit/berry bearing trees.

Grass Materials
1. Grass materials require transplanting more often. They become dense quickly. They should be split or divided as needed
2. Grooming of Sasa bamboo - Give it a "crew cut" leaving the first node above the base.
Trimming and bud nipping - Cryptomeria and needle juniper
1. Trim back to the desired height and length of foliage on each branch.
2. Transplant a couple of weeks later after the trimming.
Trimming and bud nipping - Maple
1. Check on the bud's growth EVERY DAY and nip the buds as they come out.
2. To maintain the present size and form, nip the center of the bud as the bud just begins to open.
3. To let the tree get larger, nip the bud after the second leaf opens.
4. Do not nip the buds on trees you want to enlarge the trunk of or trees in the process of healing from scars or wound.

Insects - As the weather starts to warm up, aphids will attack the tender new leaves - usually underneath the leaves. You can remove most by spraying the leaves as you water your trees. The water will knock them off. If that doesn't work, spray the underside of the leaves with Ultrafile Oil or insecticidal soap. For more details see Pest and Fungus Control Basics.
Transplanting
1. Citrus trees, gardenia, and pomegranates - Begin transplanting now
2. Crepe myrtle - Wait until April.
3. Maple - If you missed the opportunity to transplant earlier, your second chance to do so is just after bud growth comes to a rest, but before growing begins again.
4. Camellia and Sasanqua (camellia family) - Transplant immediately after blooming. Camellia roots have a tendency to form a coil, so uncoil when transplanting.
5. Wisteria - Transplant before flowering. Do not remove the seedpods after blooming, as it will keep new growth to a minimum.