California Native Plant Society
Orange County Chapter
A Few Winter Chores for Native Gardens
By Dan Songster
As the weather cools and plant growth slows we often have time off from routine garden work. So rather than sit and sip a hot mug of whatever (while leafing through promising seed catalogs), we choose not to ignore our gardens. Instead we find this to be an ideal time to get our gardens ready for the coming spring, a season full of other pleasant but demanding distractions. I hope you find the following suggestions for Winter garden activities useful.
Pruning: For those natives that benefit from trimming, this is the very best time to prune, shear, or in some cases hack away in your garden. Plants such as Desert Willow (Chilopsis linearis); Mexican Elderberry (Sambucus mexicanum); Water Birch (Betula fontinalis), and False Indigo Bush (Amorpha fruiticosa) often lack structure. During winter they are bare of leaf, making it much easier to select and prune out unwanted crossing and cluttering branches. These cuts you make in winter will direct spring’s new growth.
Shearing about one third of foliage volume suits plants such as Cleveland Sage (Salvia clevelandii), Island Snapdragon (Galvesia speciosa), and Coyote Mint (Monardella villosa). This helps create a more compact plant that is more densely flowered in spring. Lighter shearing (if any), is used on plants such as Chaparral Mallow (Malacothamnus fasciculatus), Hollyleaf Cherry (Prunus ilicifolia), and Woolly Blue Curls (Trichostema lanatum).
Some plants are a bit too vigorous for our small home gardens, but we can’t resist their beauty. Matilija Poppy (Romneya coulteri), Coast Sunflower (Encelia californica), and Wild Rose (Rosa californica) fall into this category. These do well with a severe pruning, to the ground, every year or two. (With the Romneya it’s every year for sure). California Fuchsia (Epilobium californica) also can be treated in this manner. These plants are fast growers and with the exception of Encelia, spread quickly by underground rhizomes. Care should be taken in placing these aggressive plants in your garden.
Some mature grasses and grass like plants benefit from a close cropping every year or two. The Needlegrasses (Nassela sp) and Melica Grass (Melica imperfecta) are good examples of graceful but eventually messy plants. Fresh growth is promoted by such trimming accomplished with either a sharp pair of hand pruners or a weed-eater. I have found mature Blue-Eyed Grass (Sisyrinchium bellum), to respond nicely as well, though it really isn’t needed to remain somewhat tidy. Not all grasses or grass-like plants benefit equally from such artificial grazing. Deer Grass (Muhlenbergia rigens), Purple Three-Awn Grass (Aristida purpurea ), and the lovely blue colored Red Fescues (Festuca rubra) are three which can be left alone and still look presentable. But to look really fresh in the spring perhaps a semi-annual “haircut” is warranted.
Vines: Now is a great time to trim and train your native vines. Heart-Leaved Penstemon (Keckiella cordifolia) lacks the tendrils needed for solo climbing but looks excellent along a fence. The use of adhesive discs with twist ties helps bring their blooms up to eye level. Remember, it prefers cool roots, so mulch or perhaps plant inside a shrub such as Lemonade berry (Rhus integrifolia), allowing it to grow up through the foliage and its blossoms to cascade down in late spring and early summer. Both of our California grapes (Vitis californica& V. giridiana) enjoy a good pruning about now. I usually take about a third off of young plants, just above a growth point. Older, established plants can usually be trimmed back as hard as is needed without harm. Vines pulling away from the fence or arbor should be held in place with stretch tie. Virgins Bower (Clematis sp.) looks best hanging from the lower branches of a small tree or draped down the side of a large shrub. Disobedient runners should be wound up through its “host” plant before the new, tender growth of spring sprouts.
Transplanting: Winter’s cooler temperatures and higher humidity mean less shock to the plant you are moving. Often such moves can stimulate new growth and vigor in a plant that was unhappy in its prior spot. Have the new hole dug to the right depth before carefully lifting out the plant from its old home and gently setting it in place. Install with root crown slightly above surrounding grade. Unless rain is imminent create a basin and water immediately. Do not fertilize transplants.
Wildflowers: If you have seeded your garden with wildflowers it is probable that they share their seedbed with several non-native annuals (or what I refer to as weeds). It is best to weed these areas while these weeds are small and easy to pull, and before they begin competing for the nutrients and water the wildflowers need. This is much easier if you know what wildflower seedlings look like, (as opposed to germinating weeds). Sow a small amount of each seed in a flat and label accordingly. You will see what the immature plants look like and what not to weed. Unfortunately, snails and slugs seem to prefer wildflowers, especially Lupines (and many of our young bulbs as they emerge!) So be prepared to attack them either with a bait or some home remedy you know of.
Stem Rot: One of the most important duties of the native gardener regardless of season, is an inspection of root crowns. There should be NO mulch up against plant stems (or tree trunks). Even more important, no soil should be washed up against the plants stem or trunk. This happens most commonly on inclines when a watering basin cut into the hill fills with soil washed from above. It can also occur in level situations if plants are installed too low and surrounding soil slowly washes in. Such conditions provide just the right environment for stem rot, almost sure death for the plant. Scrape away soil until you get to the surface roots of the plant. This is especially important with woody perennials and trees. If the plant is too low, raise it. Oh, and remember to knock away the front rim of hillside watering basins in the winter to allow soils and mulches to wash out instead of piling up around the plants stem.
Propagation: As the season progresses you will notice seedlings from various native plants in your garden. No, these are not weeds! Monkeyflower, Buckwheat, California Lilac, Blue-eyed Grass, Columbine, Douglas Iris, Chaparral Mallow, Lemonadeberry, and others drop seeds that will germinate unattended in the garden. They can be carefully dug, potted up, and planted in the fall in suitable locations, or given to worthy friends. Don’t forget—spring is also the time for cuttings.
Support: A bit of movement is a good thing to thicken and strengthen the trunks of young trees or shrubs, but flopping back and forth in the winter winds often causes roots to be torn from the trunk. Lightly tie your trees or shrubs to a pair of stakes placed on either side of the root ball. This gives them room to bend and flex, but limits extreme movement. When the plant’s root system is secure, untie it from the stake.
Wet Soil: Yes, there is always plenty to do in a garden; even low maintenance natives need some care. Unfortunately, during the wet season we must be cautious not to ruin the structure of our gardens soils. Most importantly we should avoid compacting our clay soils by trampling around on them when too wet. What is too wet? Here is Dan’s Test for clay soil workability. Dig out a shovel full of soil from your garden, raise it to a height above your knees and slowly turn the shovel upside down. If the soil stays stuck to shovel blade: Forget it. If it hesitates before falling: Forget it. If the soil releases from the shovel upon being turned, but does not break apart when hitting the earth, you are close, but should probably wait a day or two longer if you can. Obviously, the best case would have the soil breaking apart when hitting the ground. That’s when you dance happily into the garden, trimming, transplanting, and doing other winter chores, ahead of or in-between winter showers and getting ready for the spring.
Garden Journal: Don’t you have one? Now is a good time to start a garden scrapbook whether electronic or the old fashioned kind. (Yes, while sipping on a mug of hot whatever). Fill it with photos, plant information, the date the first Humboldt Lily blossom opened, bird arrivals, strange weather, new gardening books you have read, plants you have killed, those you have revived, recipes involving native plants, and Dan’s Soil Test results. Of course nowadays it can be most easily done on computer with digital photos, etc., but I still love the written journal with its informal sketches and ideas, taped-in plant labels, and spontaneous observations, misspellings and all. By hand or computer, a journal is one of the most useful tools for the garden and is also a lot of fun!
Garden Contact: Dan Songster at email@example.com