Cayce Hill

by UC Master Gardener Cayce Hill

Feed Your Plants What They Need

OK, who's hungry? Depending on when you're reading this article, your stomach might be growling for breakfast, lunch or dinner. Or my favorite, the late afternoon snack. Not that I always need those chips and salsa at 4:30 p.m., but there they are right there in the pantry, after all. Similarly, I have a garage shelf lined with a variety of fertilizers for my bursting backyard garden. There's the fish emulsion, “rose food,” and the more generic “plant & vegetable fertilizer,” among others. They are all labeled organic and are supposed to be good for something. But do my plants need any of it?

Truth be told, most of these fertilizers end up on my shelf because I am the neighbor that is willing to find a home for everything the other neighbors give away. Old patio umbrella? I'll reuse it. Bought a new gas grill? I'll take the old one to work. Can't take that box of flower fertilizer when you move? I might use it at some point. And so it goes until I have many boxes of many garden fertilizers. But when to use what? Just like us mere humans, plants aren't meant to eat just because there's something in the fridge (I mean garage.) Unlike us, they can't walk over and pick out whatever sounds good at the time. So here's how to give them a healthy serving of what they need at the right time. Also known as fertilizing your plants appropriately:

• Let's take the long view here. Compost is a slow-release fertilizer, and slow-release fertilizers are best. It not only adds nutrients to the soil, it also helps to retain soil moisture.

• More is not better! It is just more. Too much fertilizer can result in plant damage, excessive plant growth and additional water needs by the plant. And we all know there is no additional water these days. If you use a commercial organic fertilizer, follow the instructions on the box very carefully.

• Most woody ornamentals (think nonflowering trees and shrubs) don't require fertilizer, even at planting times. This is also true for California native plants.

• Does your plant look unhealthy? Give it some TLC! However, don't assume that it's fertilizer it needs. Unhealthy roots, poor soil conditions or improper care (gasp) are all potential culprits.

• Not all plants have the same appetite. Follow plant care guidelines carefully to be sure that you are addressing the individual needs of your fruit trees, vegetables and flowering plants.

• Don't – listen carefully here – please do not apply fertilizer directly on the trunk or crown of your trees and shrubs. It's the roots that need the food, and they can be quite a bit further out from the crown of the plant.

And I would be remiss to give fertilizer tips without mentioning the importance of appropriate irrigation. None of this plant-feeding business matters if they are not adequately hydrated. So please be a good garden host(ess) and offer a tall glass of water with that fertilizer.

References:

• Landscape Plants: Fertilizing & Watering: UC IPM
• The California Backyard Orchard: University of California
• California Master Gardener Handbook: Fertilizers.

This article first appeared in the May 11, 2016 issue of the Morgan Hill Life.

Remove all lower leaves, keeping just the top two to three sets. Allow the wounds to heal for a few days, then plant in a deep hole or sideways in a trench so that only the remaining leaves are above the soil. Roots will form where the leaf nodes were, resulting in a stronger, more stable plant as it grows.

Prepare your soil by mixing in 2 to 3 inches of compost. Add in some organic fertilizer if your soil is lacking in nutrients. For raised beds or containers, add in some fresh potting soil and slow-release organic fertilizer to ensure plants have the nutrition they need to grow and produce.

Choose an area that gets 6 to 8 hours of sunlight a day.

To avoid problems with fungus and disease, don't plant in an area where in the past three years you have grown tomatoes or plants from the same family, including eggplants and peppers.

Rotating your crops will help to avoid fusarium wilt and verticillium wilt, two common fungal diseases that affect tomatoes.

Fusarium wilt invades the plant through its roots. It is a serious problem that causes branches and leaves to become yellow and wilt; infected plants usually die. Look for plants labeled "F," which means they are resistant to fusarium.

Verticillium wilt causes leaves to yellow and turn brown before dropping off. The infection usually appears in a V-shaped pattern. Although it is seldom fatal, it reduces vigor and yield. Due to significant leaf drop, sun damage to the fruit also may occur. Buy plants labeled "V" or "VF."

Blossom end rot is caused by a calcium deficiency, often a result of irregular watering as well as a lack of calcium in the soil. Symptoms first appear as a water-soaked spot near the blossom end of the fruit. The spot will become brown, leathery and sunken, and may cover half of the fruit's surface. It's unsightly, but the fruit is still edible -- just cut off the damage and enjoy the rest. Avoid blossom end rot with regular and deep irrigation.

Another common tomato ailment is tobacco mosaic virus. It causes light green, yellow or white mottling on leaves, which may become stringy or distorted. It is usually caused by contact with tobacco products. Don't smoke or allow tobacco in or near your garden. Look for disease-resistant plants labeled "T."

Tomato and tobacco hornworms cause extensive damage to both plant and fruit. Look for black droppings or eggs on the leaves. It is best to hand-pick and discard them. If necessary, spray with Bacillus thuringiensis.

Russet mites are minute pests that can't be seen by the naked eye. Use a hand lens to identify their yellowish, conical-shaped bodies. They feed on leaves, stems and fruit, and if not controlled they will usually kill the plant. Apply sulfur dust or spray to young plants, and avoid planting near petunias, potatoes or other solanaceous plants that are often a host for the pest.

Blossom drop is caused by environmental issues. Insufficient pollination, lack of water, extremely high or low temperatures, and even smog -- all conditions we can't control -- are to blame.

by UC Master Gardener Rebecca Jepsen

This article first appeared in the May 1 issue of the San Jose Mercury News.

The benefits of Bugs

Don't squash those insects -- some may be good for your garden

by Crystal Tai / Palo Alto Weekly

While "benefits" and "bugs" seem like antonyms, certain insects actually help organic gardens be healthier.

UCCE Master Gardener Candace Simpson stands in their Palo Alto Demonstration Garden (PADG) beside phalecia, far right, a flowering plant that attracts beneficial insects. Photo by Veronica Weber.

The key is not to be too liberal with bug sprays, she said. "It is important to avoid broad-spectrum pesticides, even so-called 'organic' or plant-based insecticides, as they will kill beneficial insects as well as pests," she said.

Instead, Simpson, who teaches a class on bug benefits to gardens, suggests that home gardeners should manage pests through things like physical barriers and traps, hand removal, and encouraging natural enemies to prey upon plant parasites.

When pests do multiply too quickly to be brought under control by natural enemies, Simpson suggests choosing pesticides that have the least negative effect on the environment or any organism other than the one to be controlled. Good options include dormant oils, which might be used to smother insect eggs on dormant fruit trees, and insecticidal soaps, which might be used on a very bad aphid infestation.

Also, a bacterial pesticide called Bacillus thuringiensis, or "Bt" for short, can be used to destroy cabbage worms, according to Simpson. She said Bt wouldn't affect bees or other beneficial insects, though it can kill caterpillars.

"Fortunately, many butterflies lay their eggs on plants that are not for food," said Simpson. "So if you just apply Bt carefully to food plants that are being eaten by caterpillars, only those caterpillars will be affected. Or a good alternative is to handpick caterpillars that are eating your veggies and skip the Bt. That is what I do."

Caterpillars are not the only insects that blur the line between beneficial bugs and pests, Simpson said.

"All insects have a role to play in the ecosystem. Flies and mosquitoes can pollinate flowers, and ants eat insect eggs and also aerate the soil. Pest insects and snails, which are not insects but mollusks, and their eggs are food for other organisms," she said.

Although mosquitoes may contribute to pollination, Simpson recognizes the annoyance and danger of their bites and the reasons for eliminating them. She only advises against using a pesticide that will kill other insects as well.

"Mosquitoes can be prevented from breeding by making sure there are no containers of standing water where they can lay eggs," said Simpson. "Or by using 'mosquito dunks,' small solid cakes of a bacterial pesticide that you float in water. They only kill mosquito and fly larvae. Or we can smash them. Or wear protective clothing or use insect repellent."

Palo Alto resident Sue Luttner also likes the "smashing" approach in some cases. She said she keeps an eye on all the leaves in her garden, and as as soon as she sees holes, she checks out the backs for eggs and larvae of pest insects, and then she smashes them.

"I like to spend time in the garden, and that gives me a chance to intervene early," said Luttner. "Most of the native plants don't seem especially susceptible to insect damage, but the vegetables and the fruit trees are, so I try to stay alert to bad bugs and kill them whenever I see them."

Gardeners can also discourage exploding insect populations by intermixing different crops -- placing tomato plants in ones or twos around the garden, for example, with beans or onions or something in between, so that if one patch gets infected, the bugs won't necessarily march unimpeded right through the entire crop, Luttner said.

"I've learned not to crowd the crops, because that invites aphids. When I do see signs of aphids, I either cut off the affected shoots or pull out the plant immediately," she said.

When it comes to aphids, Palo Alto Master Gardener Callie Elliston said she would wait for ladybugs to eat them. "Ladybugs can eat 30 to 50 aphids in an hour," said Elliston. "Some of my rose buds are covered with black and green aphids. I used to hose them off with water, but now I know that if I'm patient, the ladybugs will soon come to the garden and eat all of the invaders."

Ladybugs and their larvae help control aphids as well as other pests such as beetle larvae, white flies and mealybugs, said Elliston. She said ladybugs often lay eggs on the underside of leaves and gravitate to certain plants, such as cilantro, oregano, dill and yarrow. Some local hardware stores carry live ladybugs for purchase, something that can delight child gardeners.

Another idea is to get a good look at bugs with a magnifying glass. "An inexpensive 10X hand lens is a good investment for a gardener, to get a better look at insects and their activities," Simpson said.

Even with magnification, some beneficial bugs may be hard to distinguish from pests, Simpson said, adding that she can help people learn what to look for in terms of insects during her upcoming seminar on beneficial insects on April 21, 7-8:30 p.m. at Rinconada Library, 1213 Newell Road in Palo Alto.

This article first appeared in the Palo Alto Online website, Friday, April 15, 2016. Reposted with permission.

Water-wise gardens offer plenty of color options, says gardening teacher 

by Crystal Tai / Palo Alto Weekly

Water-wise gardens, popular during the drought, do not have to be a colorless compromise, according to Roberta Barnes, who teaches science-based gardening in Palo Alto. Planned right, they can be a great source of year-round blooms.

Roberta Barnes stands in the water-wise garden beds at the UC Master Gardeners Demonstration Garden. Barnes will be leading a seminar on water-wise gardening in conjunction with the Palo Alto City Library. Photo by Veronica Weber

"Low-water plants from Australia usually bloom in winter," she said. "Then it's Mediterranean rosemary in late winter through early spring, naturalized tulips in spring, water-wise roses from late spring through summer, lavender in summer, California fuchsia in late summer through early fall, and correa from October all the way through next spring."

The seminar will cover how to design a water-saving garden with plants that bloom all year round and how to add low-water plants to a regular garden by hydro-zoning, the practice of clustering plants with similar water requirements in an effort to conserve water. The free presentation is part of a series sponsored by the Palo Alto Library and the nonprofit University of California Master Gardeners of Santa Clara County.

Water-smart gardening has already caught on in Palo Alto. Resident Jane Foglesong said she and her husband are adding native plants to their garden because they are attractive, require less water and chemical fertilizers, encourage beneficial insects and aid in the pollination of fruit trees.

"At present the native plants are integrated with other plants that need more regular watering, but over time we will add more natives, replacing those that need more water," Foglesong said.

To grow low-water plants, Barnes said it's best to start when the soil is damp, before the end of winter rains, which means there is still a little time left this year.

"One thing to keep in mind is that these plants still need a little water especially in their first year. 'Low water' doesn't mean no water," Barnes said.

As for how often one should water these natives, Barnes said, it varies from plant to plant.

Palo Alto resident Sue Luttner said her family changed their landscaping to eliminate the need for irrigation.

"When our first son was born in July of 1988 and I found myself with no time to shower, let alone water the yard, I let the lawn die," Luttner said. "We replaced it with native plants or plants native to similar climates."

Luttner called columbines and zauschneria "big winners" among the low-water plants at her house because they keep reseeding themselves. She also has plenty of herbs in her garden, including lavender and rosemary.

Palo Alto resident Pamela Chesavage said her family has a mix of natives and edibles in their front yard. The native plants needed very minimal hand watering after the initial installation and no additional water after the third year.

"I'd encourage folks to try to design their gardens themselves," Chesavage said. "Going to the class on the 18th would be a good start, but then I'd encourage folks to check out some books on California native plants, figure out which ones they like, measure their yards, and then start figuring out how to do the installation themselves."

Chesavage added that installation is by far the costliest part of changing a landscape, but it's not hard for amateurs to do.

Walking in the Master Gardeners Demonstration Garden on Center Road in Palo Alto recently, Barnes passed by a variety of low-water plants: bell-shaped correa flowers in blush pink, periwinkle rosemary flowers, yellow coneflowers and coral-pink grevilleas. In the distance, a hardenbergia vine covered the fence with pinkish purple blooms.

"In my view, a water-wise garden is more interesting than a regular one," Barnes said. "It's amazing how low-water plants conserve water with either small or fuzzy leaves. It's also fascinating to observe the differences between regular and water-wise roses."

Gardeners who aim to save water don't have to replace their entire yards.

Callie Elliston, a master gardener who lives in Palo Alto, said her family replaced the lawns with native plants that only need water once a month. But they retained lemon, apple, persimmon and pineapple guava trees, along with blueberry bushes, for screening purposes and to save on re-landscaping costs.

"Now we have a glorious spring and enjoy a sustainable garden that provides shelter to native pollinators and small birds," she said.

Elliston added a plug for fellow master gardener Barnes' seminar: "Roberta is one of my favorite speakers -- an excellent teacher, knowledgeable, with a keen sense of design."

All seven photos by Veronica Weber can be seen here.

This article first appeared on the Palo Alto Online website, Friday, February 12, 2016. Reposted with permission.