Spring is coming. Like me, you’re probably anxious to get started in your garden. We’ve gotten some much needed rain and hopefully there is more to come. As you’re thoughts turn to gardening, though, make sure those new plant choices are the right ones for your area.
Notice how much sun or shade an area gets during the growing season- from April through September. Knowing also which Sunset climate zone you are in is equally as important to make sure your garden thrives. Every year I get asked which zone the areas of Scotts Valley, San Lorenzo Valley, Bonny Doon are in. It’s confusing in Sunset Western Gardening Guide as our area has many microclimates and their map is not detailed enough to reflect this. They even show Felton as being on a ridge top instead of on the valley floor. Here are some tips to help you determine in what zone you garden. Zone 7 has the coldest winters in our area. Very high ridge tops like the Summit area and the most northern portions of Bonny Doon lie in this zone. My records show average winter lows ranging from 15-25 degrees based on 20 years of input from gardeners in these areas. This does not apply to other areas of zone 7, just those around here. Record lows have occurred during freezes in 1990, 1996 and 2007 but as gardeners we rely on average highs and lows to help guide our planting times. Spring weather comes later in this zone with the growing season mainly from April – October.
Zone 15 – this zone encompasses most of our area. Winter lows average 20-30 degrees. The valley floor of both San Lorenzo and Scotts Valley lie in this zone and are what I call "a cold 15". Cold air sinks and is trapped in these areas. Often there is damage to the tips of oleanders and citrus while gardenias and tropical hibiscus need extra protection.There are warmer parts of this zone, though, where the growing season starts in March and ends in November. These areas rarely get a freeze after March 15th or before Thanksgiving.
Zone 16 – those who live up off the valley floor but below ridge tops live in this "banana belt". Pasatiempo also falls in this thermal zone. Light frost can occur during the winter but mostly the winter lows in this zone stay above freezing. Lucky you.
That beautiful Christmas tree is now a pleasant memory and you’ve put your houseplants back in front of the windows and on the end table under the reading light. Do they look a little tired? Dusty? Yellow and leggy?
How can you make houseplants thrive in the winter when the level of light is lower and our houses are dry and heated by wood burning stoves or central heaters? What are the easiest plants to grow inside? Can they really remove pollutants from the air inside my home?
If these questions and more have you up nights in a quandry, this column is for you. You can have the interior of your house looking like the tropics in just a few easy steps.
Allow your plants to absorb as much precious light as possible by dusting off the leaves. You can do this by using a moist cloth or paper towel to wipe each leaf or place the entire plant under lukewarm water in the sink. Running water through the soil a couple of times will leach out accumulated fertilizer salts, too. Although you do want to reduce water and fertilizer during the winter months, your plant will enjoy their bath.
If you’ve had a regular watering plan, scale back. Water just enough to keep the soil from going totally dry. Poke your finger about an inch down into the soil for a typical six inch houseplant. If it’s dry, water. Be sure to dump excess water out of saucers after 15 minutes to keep roots from rotting. If your plant is in a larger pot, allow the soil to dry two inches down from the surface before watering. It’s not unusual for a plant of this size, if in a cool room, to go 2-4 weeks between waterings. Plants that need water once a month or less in winter include anything resembling a succulent ( jade plants, echiums, cactus). I water mine lightly every six weeks
Here in the Santa Cruz mountains many of us live under trees that block available light during the winter and cloudy days can further lower the amount of light your plants receive. Move plants into the best light. you have. If a plant is sitting in a dark corner, move it closer to the window. You may have to choose how many plants to overwinter based on available window light. To avoid unnecessary trauma, don’t repot a plant in winter. If you’ve acquired a new plant, it’s best to put it inside the next size pot for the time being and replant it when the growing season resumes in March or April. Most plants grow happily for years in the same pot and soil with proper fertilizing during the growing season.
Plain green leafy types do best when there’s less light. Scheffleras, arboricola, philodendrons like heart-leafed , selloum and split-leafed, pothos, Chinese evergreen, peace lily and ferns look good even in dreary conditions. They come from the under-story of jungles and grow naturally in low-light areas.
Fertilize less often. Some houseplant growers skip fertilizing in December and January, starting up again with half strength fertilizer in mid-February. Think of your houseplants as essentially dormant in winter. They need fertilizer only when active growth resumes.
Avoid cold drafts. Most houseplants can handle slightly cooler temperatures at night but detest blasts of chilly air. Avoid placing most plants near drafty, high-traffic areas such as a foyer or hallway. Ficus trees are famous for dropping leaves when exposed to temperature changes.
Many common houseplants help fight pollution indoors. They’re reportedly able to scrub significant amounts of harmful gases out of the air, through the everyday processes of photosynthesis. Some pollutants are also absorbed and rendered harmless in the soil. Plant physiologists already knew that plants absorb carbon dioxide and release oxygen as part of the photosynthetic process. Now researchers have found many common houseplants absorb benzene, formaldehyde and trichloroethylene, as well.
Some houseplants are better at removing from the air, while others do a better job on benzene; none is much help when it comes to tobacco smoke. But there are enough known plants that do a good job of removing pollutants from the air we breathe to cause us to view houseplants as more than just an attractive feature in decorating the interior environment.
If your home is old enough to be leaky and drafty, you may not need to worry about "sick-building syndrome." But if you live in a newer, energy-efficient home with windows and doors tightly sealed, or you work in a building where the air feels stale and circulation seems poor, the liberal use of houseplants seems like an easy way to help make a dent in the problem.
One is the common succulent, Aloe vera (now renamed Aloe barbadensis), also known as "medicine plant." Many people already have one in a bright kitchen window because of the soothing, healing properties its viscous inner tissue has on burns, bites and skin irritations.
Most of the plants evolved in tropical or sub-tropical forests, where they received light filtered through the branches of taller trees. Because of this, their leaf composition allows them to photosynthesize efficiently under relatively low light conditions, which in turn allows them to process gasses in the air efficiently.
Soil and roots were also found to play an important role in removing air-borne pollutants. Micro-organisms in the soil become more adept at using trace amounts of these materials as a food source, as they were exposed to them for longer periods of time. Their effectiveness is increased if lower leaves that cover the soil surface are removed, so there is as much soil contact with the air as possible.
NASA studies generated the recommendation that you use 15 to 18 good-sized houseplants in 6 to 8-inch diameter containers to improve air quality in an average 1,800 square foot house. The more vigorously they grow, the better job they’ll do for you.
It’s not too early to start planning for gifts to give for the holidays. You might be putting together something quick to give to the hostess on Thanksgiving or planning ahead for Christmas presents. Here are a couple of ideas to consider:
Colorful chard, kale, lettuce and spinach are not only nutritious and delicious, they’re also beautiful. With food prices going higher and higher , plant up of pot of living greens in a container to give as a gift. Choose a container at least 12" wide and fill with potting soil. If you plant from cell packs now they’ll be full next month to give but even if you put a couple of herbs or veggies in a pretty pot now they’ll be appreciated. Bright Lights chard would look great by itself in a glazed pot.
These leafy greens can be harvested over a long period of time by gently tearing off the outer leaves and allowing the center to continue growing. With food prices going higher and higher, even someone who has never grown veggies before will appreciate a gift like this. Plant up a couple for yourself, too, to have by the kitchen door.
For those of you that have a cool season veggie garden already in progress, it’s time to fertilize them to increase production.
Give a bouquet from your garden to dress up a Thanksgiving table. Right outside your door you can find plenty of fall leaves and berries and even a couple of flowers if you’re lucky. Mexican bush sage are still blooming as are lion’s tail, maybe a few cosmos, Japanese anemones and asters. Ornamental oregano holds up well , too, especially the variety Santa Cruz. Foliage can be a key player and might be found from smoke bush, ornamental grass, purple hopseed, crape myrtle, Chinese pistache, oaks, maples and liquidambar. Dogwood leaves would be beautiful as would ornamental pear. Berry accents are a staple for a fall bouquet and you might have nandina, cotoneaster, hawthorn, dogwood or crabapple in your garden. Go out and fill a brown shopping bag with whatever strikes your fancy to create a beautiful fall bouquet to give or dress up your own table or entry. Your arrangement should last about 4-7 days in a moderately cool room.
I like to start hyacinth bulbs in the refrigerator in pretty colored hyacinth jars to give as gifts. Make sure the water barely touches the bottom of the bulb or it may rot. It usually takes 6 weeks or so for the jar to fill with roots before you bring it out and place in a bright spot gradually so it can acclimate to the light. Their fragrance is incredible.
Forcing narcissus bulbs is simple and make a classic gift that can perfume an entire room. Flowers take 4-6 weeks from the time you plant them to set buds so start them now. You can plant them in a shallow pot filled with potting soil or nestled slightly in pebbles or sand in a water tight jar. An interesting container from the thrift shop would make your gift unique.
Allow the plants to grow under cool, bright conditions to keep their stems compact and strong. Stake flower stems if they start to flop over or you can give them a diluted solution of alcohol to keep stems and leaves 1/3 to 1/2 shorter than those growing in plain water. The key thing is to let the bulbs develop roots in water and stones to anchor the roots as usual until the shoots rise 1 to 2 inches above the top of the bulb. Then pour off the water and replace it with a solution of water containing 4 to 6% alcohol such as gin, vodka or rum. To get this percentage from an 80 proof distilled spirit, you would need 1 part liquor to 7 parts water. This yields a 5 percent solution.
Use this alcohol-water combination when you need to add water to the bowl. Cornell scientists say rubbing alcohol also works but because it is typically 70 percent alcohol, less is needed, just 1 part to 10 parts water. I wrote about this interesting method last year but thought you might want to be reminded abut this handy tidbit of information if you’re going to start for yourself or to give as gifts.
Geranium, penstemons and petunias sometimes become infested by budworms. Foliage may be chewed, flowers may open tattered and full of holes or appear dried up and not open at all. Tiny black droppings on the foliage are left behind. The striped caterpillar larval form of a native moth is a close relative of the corn ear worm, the tobacco or geranium budworm. Moths lay eggs singly on host plants. After hatching, the caterpillars chew fully opened flowers and occasionally dine on the leaves. Spraying early on with organic BT is effective if done before the worms burrow inside the flower buds. Remove dried up buds and flowers that may harbor the caterpillars and pull up and destroy ragged, end-of-season petunias that my have eggs sticking to the plant remains. There may be two generations per year so preventative spraying with BT may protect established plants of geraniums or penstemon.
If your fuchsias aren’t blooming and the leaf tips look curled up and deformed, your plants are infested with fuchsia gall mite. First discovered on the West Coast in 1980, it is often mistaken for a disease because of the way it distorts and twists fuchsia leaves and flower buds. The damage caused can be debilitating. The leaves curl and distort so much that normal photosynthesis is disrupted and weakened plants fail to bloom Infested plants usually recover if further mite damage is controlled. Prune off all distorted foliage and buds. This may be the best method of control as petroleum oil or insecticidal sprays need to be made every 4-7 days to disrupt the mite life cycle. Neem oil is not recommended for use on fuchsia flowers.
There are several gall mite-resistant fuchsias, both hanging and upright, that are very bit as showy as the traditional fuchsia varieties. if you have been plagued by fuchsia mites, try growing one of these instead.
Lately I’m getting a lot of requests for garden coaching. The economy probably has something to do with it. People want to know what plants will thrive in the different areas of their gardens or why something isn’t working. Who can afford to waste $ on the wrong plant in the wrong location? When I make house calls there are several problems that seem to keep cropping up. Maybe one of these tips will help make your garden grow.
If your soil looks like a sandy beach, amend it each time you plant something new with organic matter like compost or planing mix. Then be sure to mulch the surface to preserve precious moisture and soil structure and keep roots cool. Yearly, add organic mulch around existing planting keeping the immediate area around the crown of the plant open. If your native soil is just a little on the sandy side, you may not need to amend the soil much before planting but don’t forget that all important mulch. Crushed gravel or cobbles uses as a mulch holds in moisture the same way as bark or compost.
Those of you who live under redwoods may have the opposite problem- heavy clay soil, dense enough to make pottery. Surprisingly, adding organic matter to these soils solves this problem, too. The key is preserving the soil structure fterwards by mulching so it doesn’t pack down every time you water or during the winter rains.
Not watering deep enough or watering too often
Sure there’s a period of time when you first plant something that you need to water more often until it’s established but even then watering every day is rarely needed. As a rule of thumb, water a new 1 gallon plant when the top 1/2 " – 1" is dry. A newly planted 5 gallon container will need watering when the top 1 1/2 – 2" is dry. A tree or large shrub planted from a 15 gallon container needs watering when the top 2-3" is dry. Hot days as well as shady locations vs sunny sites will all affect how long you can go between waterings. When you do water apply enough to water the entire root zone deeply. If the water doesn’t penetrate 1-3 ft down, depending on the plant, it will suffer and even die. Drip systems are great if you have them set properly. Don’t waste water by having your timer set for 10 minutes every other day. If you have 1 gal/hour emitters that’s less than 3 cups of water each. How deep is that going to penetrate? Set your system so that each zone gets enough water for long enough to really count. This applies to established low-water use plants, too. They need a deep soak every 2-4 weeks. One last tip on drip systems: make sure the emitter isn’t right next to the stem or trunk. Plants need water applied at the drip line where the feeder roots are located, not drowning the crown. Move it out as the plant grows and the dripline enlarges.
If you need to plant in gopher baskets, make sure you eliminate the air pockets between the root ball and the side of the basket. Many times I’ve dug around a plant that is not doing well only to find big air spaces down the side of the basket or the planting hole where the soil was not properly tamped down. The roots on that side of the plant will die under these conditions and possibly the whole plants will be killed.
Right plant-wrong place
Become familiar with the sun patterns of your property during the growing season- spring through fall. Many of us don’t have winter sun and lots of plants can adapt to this but they are more exacting when it come to light requirements during the growing season. It gets pretty hot around here so a spot with sun in the afternoon is fatal to a plant that is not a sun lover. For those optimists out there, those delicate rays that filter through your trees do not constitute a sunny garden. You have bright shade and there are lots of great plants that can provide color and texture in your shady garden. Make sure you follow tip #1 in both spots so your plant isn’t fighting crummy soil on top of everything else it has to handle.
Hopefully, these tips will help make your garden grow better.