Buzz Bertolero

Tomato Tips & Strawberry Fields Forever

May 31, 2013 by Buzz Bertolero Leave a Comment

Q. I have two strawberries on separate plants that have small leaf-like structures growing out from the surface of the berries. What causes this and are the berries okay to eat?

A. Strawberries are one of the few berries where the seeds form on the outside of the fruit; hence, they are not considered a true berry. True berries form their seeds inside the fruit. The leaf-like structure is an immature leaf that has germinated. Typically, the seeds on strawberries are sterile but on rare occasions they do sprout. I can’t tell you what triggers this event. All of the strawberry plants available today are propagated from vegetative cuttings or division. But, you can purchase seeds for both alpine and traditional strawberries online. The seeds formed from these variety maybe more incline to sprout on maturing berry. Strawberry leaves are non-toxic so I just rub them off when they appear. Strawberry leaf tea is most commonly used to improve digestion throughout the digestive tract

Q. In April, I planted several Heirloom, Brandywine tomatoes. The plants are producing plenty of flowers, but they’re drying up and falling off before they set fruit. Could you tell me what might be causing this?

A. It is early for the fruit set on Brandywine tomatoes so I wouldn’t be pushing the panic button just yet. It’s not unusual for the first group of flowers to fall off and fail to set fruit. You should expect to see tomatoes by the end of the month or early July. Tomatoes primarily fail to set fruit because of cool nights and or the lack of pollination. Another issue can be excessive nitrogen causing the plants to grow rapidly. I don’t think this is an issue since there was no mention of any excessive growth. Tomatoes like constant nighttime temperatures above fifty-five degrees. The marine influence is a major factor in delaying the formation of tomatoes. The closer you’re to the water the more problematical it can be. Warm days generally translate into warm nights inland so the fruit set occurs as expected. You need to be selective as not all tomato varieties produce well in all of our many microclimates.

Unlike other edibles, fertilization and pollination does not occur simultaneously in tomatoes. They’re two separate events. Once pollination occurs a pollen tube must form to transfer the pollen down to the base of the flower where fertilization occurs and tomatoes form. The cool nights slow the tube formation. After four days, the flowers drop off whether or not fertilization has occurred. The chief pollinator of tomatoes is the wind and not bees. We normally have enough of an afternoon breeze to do the trick; however, poor air circulation can still be a problem. You can aid Mother Nature by gently shaking the plants. The best time to do this is midday. Another option is to spray the open blossom with Blossom Set. It is successfully used on melons, squash, and cucumbers where pollination is a problem.

Buzz Bertolero is Executive Vice President of Navlet’s Garden Centers and a California Certified Nursery Professional. His web address is www.dirtgardener.com and you can send questions by email at dirtgarden@aol.com or to 360 Civic Drive Ste. ‘D’, Pleasant Hill, Calif. 94523 and on Facebook at Facebook.com/Buzz.Bertolero

Why Fertilize?

May 4, 2013 by Buzz Bertolero Leave a Comment

Q. As a new gardener I was wondering why one must fertilize container plants frequently. If you buy good plants, have good soil and take care of them, why then is fertilizer necessary? In addition, why does 0-10-10 help plants bloom? Won’t they bloom on their own?

A. You’re probably correct about having to feed often but only if you’re talking about a few weeks or maybe a month for container plants and a bit longer for landscape trees and shrubs. Plants require nutrients to grow and thrive without them they will struggle and eventually die. One of the functions of roots is to absorb nutrients. The nutrients are then transported upward throughout the plant. Nutrient depreciation or loss in containers is rapid because every time you water, which is frequently, water carries them away as the container drains. It’s important to recognize that container plants have perfect drainage verses those planted in our clay or adobe soil that drains poorly. In addition, the roots are restricted to a pre-defined area, the pot size while those plants in the ground have plenty of room to expand beyond their canopy. Soil microorganisms are also present absorbing organic matter and converting them into nutrients. Overtime the volume of soil disappears and is replaced with roots. The three primary elements necessary for plant growth are Nitrogen (N), Phosphorus (P) and Potassium (K), also known as NPK. There are ten or more secondary elements like Boron, Iron, Sulfur, Copper, Magnesium and others needed in lesser amounts. Nitrogen is necessary for growth and lush green foliage. It leaches quickly from soils because it is mobile element so it needs to be replaced frequently. Phosphorus and Potassium are for fruit and flower production, aids in the general plant hardness, and remains longer in our soils. The nutrient/fertilizer analysis is on every bag of fertilizer and is expressed as a percentage. The first number is always Nitrogen (N), next is the Phosphorus (P) and finally Potassium (K). On the back of every fertilizer bag, you’ll find a detail listing of all the elements including the secondary ones. Some plants fail to bloom when they are growing too vigorously while others are not affected by the growth cycle. Light and temperature are two other strong influences in flowering. Low or no nitrogen type fertilizers like 0-10-10 help plants bloom and are applied during the winter months to Bearded Iris, Citrus and others. Gardeners will switch to 0-10-10 with Fuchsias, Tuberous Begonias and other flowering once the desired size has been reached to maximize color. Today, we’re spoiled as we have many different types of fertilizers choices, such as time release, organic, water-soluble and synthetic. They’re all good answers but which one is the best? The Nursery Professional at your favorite garden center is the resource for plant specific fertilizers and fertilizing for you and your yard.

Buzz Bertolero is Executive Vice President of Navlet’s Garden Centers and a California Certified Nursery Professional. His web address is www.dirtgardener.com and you can send questions by email at dirtgarden@aol.com or to 360 Civic Drive Ste. ‘D’, Pleasant Hill, Calif. 94523 and on Facebook at Facebook/.com/Buzz.Bertolero

Orange and Lemon Trees / Wisteria

March 29, 2013 by Buzz Bertolero Leave a Comment

Q. We have a mature orange and lemon tree growing next to each other. The lemons are fantastic but the oranges are extremely sour. Our gardener feels that the orange is cross-pollinating with the lemon tree. How can we make the oranges taste better?

A. The rational that lemon and orange co-mingle to produce sour oranges has been used for decades. The reality is it is just a myth. Most citrus are self-pollinating so they don’ require a second variety for cross-pollination, however, there are some exceptions such as the Clementine Mandarin Orange. Most of the pollination is done by Honey Bees looking for nectar or other flying insects. In addition, seedless citrus varieties such as Washington Naval Oranges produce mostly parthenocarpic fruit. Parthenocarpy is the ability of plants to develop fruit without pollination, which means no or very few seeds because the male part of the flower is sterile so no pollen is produce. That being said, if oranges and lemons could mate and this is a very big ‘if’, the maturing fruit would never be affected. The result of the crossing would be in the seeds that then have to be germinated. This is called genetics. Hence this age old answer to sour fruit can’t possibly happen with a maturing crop of oranges. Not every, Bay Area garden is suited for growing oranges. The closer you live to the water the more challenging it is. Sour oranges are caused by not enough summer heat or by harvesting the crop to early. Oranges require six hours of direct sunlight April through October, Naval and Valencia Oranges flower in the spring and turn an orange color in November. Naval Oranges ripen December through March while the Valencia Oranges do not mature until the following June or July. Unlike many other types of fruit, most citrus can be left on the tree without becoming over ripe. If you’re not sure what variety you have, leave the oranges on the tree and taste them periodically throughout the year.

Q. We would like to raise the soil level about one foot around four very old and lovely-blooming Wisterias. Our first choice would be to bury each plant. Is that possible? Our second option is to dig the plants up and replant them. The last thought is to install plant wells around each plant. What would you suggest?

A. Of the three options, the least desirable is to bury the plants by raising the soil level. Actually, this is not advisable at all as it’s a sure way to kill them. The Wisterias could be transplanted to a new location but given their age it may not be feasible. I think the most practical is to build permanent plant wells around each plant. They should extend from the trunk to beyond the drip line. This is where the majority of the roots are located. You can use a variety of materials such as railroad ties, concrete blocks or moss rocks to hold back the soil.

Dirt Gardener – Sterilizing Soil

March 6, 2013 by Buzz Bertolero Leave a Comment

Q. Is there a way to sterilize soil other than baking it in an oven? I like to recycle my old soil from containers. I first sift the soil and then store it in large plastic cans. Unfortunately, the weed seeds are not killed when stored for a year or so. Do you have any other suggestions?
A. A household oven isn’t a very practical method of sterilizing soil. I don’t think it was ever a popular or widespread practice. Storing soil for a year or more in the dark isn’t very effective either. Soil needs to be heated first to effectively kill the weed seeds, soil insects and other soil pathogens. The sun is a far more common method of sterilizing soil. This process is called soil solarization.

Soil sterilization is a sensible solution for large areas or small quantities of soil. Black plastic or a commercial tarp is the only equipment necessary. The used soil is place in a pile, pre-moisten, and then cover it sealing the edge so the moisture doesn’t escape. You should select an area that gets eight to ten hours of direct sunlight a day. It should bake for six to ten weeks June through September. The weeds seeds are killed as the temperature rises, converting the moisture to steam. You will control a fair amount of the problems but not one hundred percent. You could accomplish this in a plastic container but I think covering the soil is more effective. Once it’s been sterilized and aired out, you can store it in seal container indefinitely.

Another way to control weed seeds around desirable plants in containers or in the ground is with pre-emergent herbicides. There are granular pre-emergent products available such as Pre-Seeder Weeder or Preem. I’d ask the nursery professional at your favorite garden center for a recommendation. Weed control in a landscaped area is best accomplished with two to three inches of mulch. Mulching prevents the weeds from germinating as it blocks the sunlight from reaching the soil Weed Block and similar products are available; however keep in mind every couple of years you need to remove the old mulch and refresh it will new. The old mulch can be recycled and used as a soil amendment. In summary there are many other desirable methods of sterilizing soil available other than using your oven.

Dirt Gardener – Planting Potatoes by the Moon

February 5, 2013 by Buzz Bertolero Leave a Comment

Q. As a kid, my grandmother would always plant potatoes by the moon. Is that still done today; and if so, when is the right time to do it?

A. ‘Gardening by the Moon’ is still alive today, but on a limited basis. It’s being rediscovered by a new generation of gardeners who are using an old school approach to gardening. They’re into organic cultural practices; such as composting, compost teas, cultivating for weed control, organic disease and pest controls, etc. The moon dictates what and when to do almost all fundamental gardening activities. The influence of the moon and its different phases is twofold. One, the pull of the lunar gravity along with the increasing and decreasing light of the moon affects plant roots and leaves. Second, gardening activities, when to weed, what to plant, etc., is determined by which of the Zodiac signs the moon is traveling through. From a scientific standpoint, the ‘Gardening by the Moon’ methodology hasn’t been proven or disapproves, so you’ll find supporters and those that think otherwise. That being said I do publish a weekly ‘ToDo’ based on the moon at www.dirtgardener.com. Personally, I’m not a strict follower of the activities. Concerning planning potatoes by the moon, this is not the weekend to plant. Your best and only opportunity is month is March 9-14 under the sign of Scorpio, Libra and Sagittarius and just before the beginning of the four-quarter on March 14, which is a resting period. Potatoes are one of the easiest short-term crops for a home vegetable garden and are great to involve kids with. They can be planted in traditional raised beds and containers. Some of the more unorthodox planters include spare tires, a bed of straw or a bag of commercial potting soil or planting mix. Besides the usual amendments and fertilizer, it’s recommended to add Sulfate of Potash for the extra Potassium. Seed potatoes are recommended to plant over those found at the supermarket. The yield from the supermarket purchased potatoes is unpredictable, as they have been treated with a growth inhibitor to limit the new shoots. That is not the case with seed potatoes so you get a guaranteed yield. You should cut the potatoes in half or quarters depending on the size. The freshly cut ends should be dipped into Soil Sulfur to prevent rotting and let to air dry for twenty-four hours. Your favorite garden center now has red, white and the large russet seed potatoes available for planting. Last year and again this year, I used the Gardman Potato Tubs grew them on my deck all summer long. They’re the perfect compliment to an Earthbox for home grown vegetables in containers on decks, patios and balconies. I planted around the first of February and harvested fifteen pounds of potatoes in August. You can follow their progress on my facebook page, facebook/Buzz Bertolero.

Pruning Roses

January 14, 2013 by Buzz Bertolero Leave a Comment

Q. After pruning my roses, is there any special winter fertilizer I should apply to my bushes? In addition, what should I treat the bare stems to minimize the Rose Rust, and Black Spot this year?

Ans. While there isn’t any special type of winter fertilizer for roses, they do need to be fed but it’s a bit early to start. I’d wait another month or when the new growth is about one half inch long to make my first application. There are a lot of great fertilizers available for roses, so no one brand or type is the best. Dr Earth is a fabulous, organic fertilizer. Miracle Grow is perfect for those that love to fertilize often and for those that fertilize infrequently like me, there is Osmocote. Osmocote is a time-release fertilizer that is applied every four months. Roses are heavy feeders, so whatever fertilizer you choose, reapply it regularly right through October. To start your rose disease control program. I’d spray the canes with Bonide Copper Spray but first strip off any of the remaining leaves and remove all the debris from under the plant(s). The spores from Black Spot, Rust and Mildew can over-winter in this material. This should be done sometime in the next couple of weeks. Ideally, before the new growth is too far along. This is a preventive measure to remove any of the local sources for the diseases. It sort of sanitizes the area. The spores of Rose Rust, Black Spot and Mildew are air borne, so there is a better than average probability that they’ll return with wet, damp and rainy conditions. The length of time moisture remains on the leaves after the sun goes down triggers the problems. The damaged leaves show up about ten to eighteen days after being infective. Last spring, the rose diseases were a big problem almost until Mother’s Day, because of the wet spring we had. So applying a rose fungicide to foliage is recommended and again there are a lot of choices. There is no fungicide that will eradicate the diseases, they only control them: hence, depending on the weather, repeat applications must be made until the rainy season ends. Also keep in mind, to be effective, the fungicide must be on the foliage before the moisture arrives not afterwards. This can be challenging with all the other things that can be happening during a week. My solution is Bayer Advance All In One Rose Care. It feeds my roses, provides a systemic fungicide for six-week control of the rose diseases, and finally as a bonus takes care of the Aphids, Thrips, and Spider Mites. Bayer Advance All In One Rose Care is available in a liquid, which doesn’t have to be sprayed on the foliage and easy to apply granules. Unfortunately, Bayer All In One Rose Care is not an organic solution and I only use it in the spring until the rainy season has concluded. You can certainly separate these into individual tasks but I prefer one and done.

Wisteria and Drichondra

December 6, 2012 by Buzz Bertolero Leave a Comment

Q. I have a well established, twenty-year old Wisteria climbing up the front of my porch. By now, the growth is out of control. Can I trim it back during the year without jeopardizing next spring’s blooms? Also, how might I help increase the flowering, as there isn’t an abundance of blossoms?

A. There is a reluctance of gardeners to prune deciduous vines, fruit trees and roses once the primary winter pruning season is completed. When quizzed why not the most common answers are, “it may die,” or, “it will stop blooming.” The reality is, plants never die from such pruning practices; however, flowering issues may develop related to off-season pruning depending on the species. Spring flowering plants and trees such as plums, pears, cherries redbuds, lilacs and wisterias are best pruned after flowering. The only harm in pruning earlier during the winter months is the removal of the spring flowering wood that reduces the show of color. Wisteria as you have mentioned is an aggressive grower, so an annual pruning is required to keep them contained. It is okay to continually shape the plant during the growing season by pruning off or back any of the growth that is growing in the wrong direction. Wisteria blooms on the second year and older wood or shoots. With my Wisteria, I’m forever cutting the new growth out of the eves of the house, floodlights and a nearby orange tree. I’m not worried about the flowers as there will be plenty of growth for the Wisteria to bloom on next spring. You can improve the flowering by lowering the soil pH. The pH scale is from one to fourteen with seven being neutral. Any reading above eight is said to be alkaline while soils below seven are said to be acidic. Wisteria likes a soil pH around six to six point five. You can purchase a simple pH kit at your favorite garden center. Since our soils are somewhat alkaline, I’d apply Soil Sulphur or GreenAll pH Adjuster to lower the soil pH. With the beginning of the rainy season, it’s an excellent time to apply these products. Soil Sulphur or GreenAll pH Adjuster is also beneficial to Blueberries, Azaleas, Camellias, Rhododendrons, Gardenias, and other shade loving plants.

Q, I recently sowed Dichondra seed between the stepping-stones in my backyard. I’m now noticing some thin grass starting to pop up. Is there a weed killer that you can use on dichondra to control weeds. I’ve heard that some weed killers won’t work because Dichondra is actually considered a broadleaf plant and the weed killer would kill the dichondra as well. Is this correct?
A. Yes, Dichondra is a broadleaf plant and not a grass. Thus any of the broadleaf-weed killers or herbicides would wipe out the Dichondra. But all is not lost. Ortho Grass-B-Gon is a selective herbicide for grassy weeds in broadleaf plants. It can be used on Dichondra for the unwanted grass. You’ll then have to manually remove any of the broadleaf weeds that sprout.

Dirt Gardener – Pomegranates

November 2, 2012 by Buzz Bertolero Leave a Comment

Q. Last winter I planted a bare root pomegranate. It has done very well, in fact it has nearly doubled in size but the growth is very leggy. Should I cut it back now to encourage branching, or wait until it is dormant? By pruning now will I cut off any potential fruit?

A. Pomegranates are pruned usually during January and February but you can start earlier when the leaves start to drop. They’re grown as a medium size shrub or a multi-stem small tree. There are three things you need to do when pruning pomegranates, eliminate the dead wood, remove the rubbing and crossing branches and then shape the plant by reducing the length of the growth. That being said, pomegranates naturally have long arching branches that gives it an arching, vase like form, so heavy pruning can alter the plant’s aesthetics. You preserve the natural tree look by removing branches to the trunk or larger limbs instead of an overall shearing. The canopy should be thinned out every three years, regardless of the growth form. Of course all of this is a judgment call on your part, as there are many correct methods of shaping depending on the location and the plants surrounding it. Pruning can affect the size of the crop as the fruit forms on new wood. Hence, it’s important to feed annually in the early spring with a complete fertilizer to encourage the new growth.

Pomegranates are one of the easiest fruits to grow. The Spaniards introduced them into California in the sixteen-century. They’re native to southern Europe and spread throughout California with the establishment of the missions. Today they’re being rediscovered by a new generation of gardeners just like blueberries. They’re popular for the following reasons. Pomegranates are high in antioxidants and easy to grow in a wide variety of soils or in containers. They’re somewhat drought tolerant and not affected by many pests or diseases. The bright orange tubular flowers attract hummingbirds and are a popular plant choice for bonsai. Wonderful and Eversweet are the two most widely available varieties, but there are many others. And finally, you’ll also find Punica Granatum is a non-fruiting landscape shrub that is available in our area. It grows to four feet with a three-foot spread, so it’s very adaptable to small yards.

Q. The onions I planted this year had a problem. Seed stalks develop when the plants were still very small. Why do onions go to seed so early?

A. When onions go to seed, it’s called bolting. The primary cause of bolting in the Bay Areas is weather related stress due to changes in temperature. Onions are best planted in the fall and late winter through the early spring. Onions planted April through June go to seed the first time the temperatures climb into the 80’s. Onion sets are now available while the sweet Bermuda Onions plants that are Stockton Red, Torpedo Sweet Yellow and White, in early November.

Japanese Maple and Netherland Dwarf Rabbits

October 9, 2012 by Buzz Bertolero Leave a Comment

Q. I have a three year-old red Japanese Maple that looses it red leaf color. It leafs out with beautiful red leaves but by the end of summer they’re a dull green. What do I need to do to help this tree hold its color?
A. It is quite common for red leaf Japanese Maples to lose their red color by the end of summer. It is due to the day length, the level of stored sugar in the leaves, the sugar depletion rate and temperature. The sugars are produced by photosynthesis during daylight hours, as sunlight is absorbed and then stored in the leaves. The amount of sugar does vary by variety. The maple then uses for normal respiration and metabolic functions the sugars. The depletion rate, also called respiration, is a function the temperature. The red color is the strongest in the spring when the sunlight hours are increasing and the temperatures are still cool. This results in high sugar production and low consumption. The longest day of the year is June 21. As the days get shorter in mid to late summer the production of sugar decreases and with higher temperatures the consumption of sugar increases. This results in a net loss of sugar and as a result the red color fades to green as the sugar is depleted. Some cultivars produce more sugar or consume less and these varieties stay red longer. A tree planted in shade produces less sugar yet consumes the same as one planted in a sunny location; thus the loss of the red color is sooner in the summer. Here in the Bay Area, our summer fog or overcast has the same effect as shade. Generally, the red color of Japanese Maples lasts longer in the northern latitudes than in the southern areas because the hours of daylight are longer during the summer with usually cooler temperatures resulting in more sugars remaining in the leaves later in the year. So the frank answer as to what you can do to help keep the red color longer is nothing, so enjoy it while it last during the spring of the year.

Q. I’m landscaping my backyard but have three Netherland Dwarf Rabbits that live in the yard. They seem to eat everything but I don’t want to cage them up. Do you have any suggestions?
A. Unfortunately, I don’t have any solutions that are practical. Domestic or wild rabbits are a problem much like deer. They eat almost everything as you have found out. Rabbit repellents are available but they are water-soluble and the repeat applications do become tedious during the rainy season. You’ll have to make a choice between the rabbits and the plants. I think the best answer is segregated the rabbits from the rest of the landscape. If you do be sure to bury the containment wall about twelve to eighteen inches below the soil surface as the rabbits will escape by digging under the barrier. The other answer is a containment area that is off the ground. Caging the rabbits may be your best solution you have.

Discolored Potatoes

September 3, 2012 by Buzz Bertolero Leave a Comment

Q. When I harvested my potatoes, I noticed that some of the potato skins had areas with a green discoloration. I’ve been told they’re poisonous. Should I discard the green potatoes or the entire crop?

A. Potatoes are an edible tuber that forms underground. It’s important to keep the tubers covered during the growing season so that the maturing potatoes are not exposed to sunlight. The potato skin turns a green or a greenish blue color when exposed to light. The damaged area could be large or small depending on the exposure. The green portion of the skin contains toxins and should not be eaten but that isn’t the issue. The greenish coloration is merely a sign that a potato has been exposed to light, prompting it to produce more chlorophyll, and chlorophyll is not toxic to humans. What creates the problem is that the light exposure also produces a substance called solanine, a glycoalkaloid, which has been shown to be toxic when consumed in great quantities. Solanine is a natural defense mechanism of a potato to ward off fungus and pests. It can also be triggered when a potato is bruised, so you should discard these potatoes. Since solanine collects only under the skin and not throughout the potato, it is safe to peel away the skin and a thin layer of white flesh before cooking; however, I would discard any potato that is entirely green. Again, this is an individual problem that doesn’t affect the other potatoes you harvested, so enjoy them. Potatoes should be stored in a cool dark location. I’d used brown paper bags or a cardboard box and then covered them with newspaper. Dark plastic bags can be used, however you’ll need to punch holes in the bag for air circulation. This keeps the potatoes dry and prevents mold from forming. The kitchen counter is not an ideal location except for a short-term use. Next year when you plant, you can avoid the problem by adding potting soil or other types of organic matter to the potatoes for a couple of months after planting. This is sometimes referred to as ‘Hilling’ and it’s not unusual to add a foot or more of material. Scientists have determined that an adult would have to eat about four and half pounds of light-exposed potatoes to reach toxic levels of solanine. Potatoes are, to a certain degree poisonous, though not in a deadly manner, and usually not enough to make anyone sick. The leaves of the potato plant contain high levels of a toxin, and are direct relatives of the deadly nightshade plant, as are tomatoes. In the US, it has been over fifty-years since any one has succumbed to potato poisoning, so the risk is very low. And finally, according to Wikipedia, deep-frying green potatoes at high temperature at three hundred an sixty degrees effectively lowers the level of toxins but boiling them at two hundred twelve degrees has no effect.