Gardening Q&A


Pistacia chinensis

I live in Northern California along Interstate 80, and I see a lot of brilliant red trees along the freeway. What are they?

Anyone who has driven along Interstate 80 between Sacramento and Auburn in autumn can't miss the scarlet foliage planted along many of the on and off ramps. The color is screaming red. On a cloudy day, it's positively luminous. It's the Chinese pistache (Pistacia chinensis), and while it is related to the pistachio, it doesn't produce nuts. The tree grows to 25 or 30 feet tall.

It's very adaptable and settles just as happily in a yard with regular water and decent soil as it does in places where it gets no care at all. The female Chinese pistache trees bear small green and red berries. They can reseed, but I've never found them to be invasive. Choose pistache trees in the fall so you can see their beautiful colors.

I want to save tomato seeds this year. How do I do it?

The heirloom tomatoes in my garden are perfect for saving seed. Tomatoes are self-pollinating, so I don't have to worry about them being pollinated from the neighbor's tomatoes.

There are two schools of thought for saving tomato seeds:  

  • Traditionally, you wait until the tomato is really ripe, past its prime for eating—soft, squishy and splitting. Scoop out the seeds and put them in a container for a few days to ferment. They'll get a frothy, scummy covering on the top. Next step is to rinse that off, getting the seeds clean, and spread them on a paper towel to dry. Once dry, package them, label them and store them in a cool, dark place until next year.
  • Then there are the tomato-seed savers who simply scoop out the ripe seeds, clean them, spread them on a paper towel and write down the variety, let it dry, put it in a plastic bag and that's it.

Both sides say their method works well, allowing you to grow your own starts next year. If you try it, please let me know how it goes!

See how Pat answered your questions earlier this year.

 

I do enjoy sunflowers and need a tip on how to keep bugs and/or rabbits from eating the seedlings before they become mature enough to grow large. I live in the Inland Empire in Southern California.

Pam

Dear Pam,

Thanks for writing. Seeds started directly in the ground where you want them to grow are certainly subject to insects and browsing animals. One giant pumpkin grower I know in the Sacramento area has trouble with rabbits nibbling his seedlings. He fashioned cages out of remesh (in essence, made a circular cage), and put one around each plant. Then he wrapped plastic around the bottom 6 or 8 inches of the outside of the cage. Problem solved.

We had skunks coming in the garden at night digging in the beds looking for grubs. They'd disturb all of the seedlings and vegetable plants, and after a few days of being dug up every night, the plants died. We finally put a small picket fence around the vegetable garden.

You can also protect each seedling with something as simple as two sticks with a piece of sunshade over them.

I'd also suggest starting your seedlings in pots or flats and letting them get a bit bigger before putting them out. Older seedlings are less susceptible to cutworms, earwigs, etc. Chances are that earwigs or slugs are eating the seedlings. If the problem is slugs or snails, you can sprinkle diatomaceous earth around them (has sharp edges and the slugs won't crawl over it). There is a product called Sluggo Plus that kills slugs, snails and earwigs, and is nontoxic to people and pets. I've used it with great success.

Good luck, and let me know what works!

Pat

How can I protect young plants and seedlings from the sun?

I put inexpensive tomato cages around a few of the plants, then put a black plastic nursery flat on top. The shade moves around the bed as the sun changes position, so all of the young plants and seedlings get some protection, but also get plenty of sun so they grow strong.


What's the best way to make sure potted plants get enough water?

Sometimes during the hottest days, if the pots are in the sun, you might have to water twice daily. I use a soft-rain nozzle, and I water until the water comes out the bottom of the pot, then I water the plant again. Too many people think if they sprinkle the plants, they are giving them enough water. They are not. Remember, plants in pots are more exposed to sun than those in the ground: The pots heat up, and there really isn't enough soil, unless the pot is huge, to protect and insulate the roots. So you may have to water pots in the sun more than once a day.

See how Pat answered your questions earlier this year.

About Pat Rubin, California Bountiful's gardening expert


Pat Rubin

For Pat Rubin, gardening is more than just dirt and plants. "It's about history, romance, adventure and people," she says. "And it should be fun."

California Bountiful's gardening columnist has lived and chronicled this fun, hands-in-the-dirt approach for years—and for additional publications including Fine Gardening, Pacific Horticulture, Christian Science Monitor, Family Circle and The Sacramento Bee. Pat has also volunteered as a Master Gardener, speaks to garden clubs and appears regularly on gardening radio shows.

Need gardening advice? Ask the expert!

Send your questions to gardening@californiabountiful.com

My yellow zucchini plant called Butterstick has unusual, tightly curled leaves on one of the bigger stems branching off the main plant. The zucchini is bumpy and deformed. The rest of this plant is normal, but this one branch is producing most of the zucchini. I checked the leaves for mites and other insects, but didn't see anything that could be causing it. Is it squash leaf curl? If so, will it affect the rest of the zucchini plants and garden crops?

Susan 

Dear Susan,

It sounds like squash leaf curl, which is a virus carried by whiteflies. They are sap-sucking insects, and have infected your squash plant. There is no cure, only prevention. Often the squash produced by the affected parts of the plant will be stunted or misshapen.

If only a part of the plant is affected, remove that part. Toss it in the garbage. You can harvest the squash from the rest of the plant.

After the season is over, toss the entire plant in the garbage, even if the rest of it does not show signs of the virus. Do not use it for compost.

You can hang sticky traps for whitefly. Also, remove all weeds growing around the vegetable garden so the whiteflies don't have a place to hide or overwinter.

You can call your local University of California Extension office (look under Farm Advisor in the county section of your phone directory) and talk to a Master Gardener.

Best of luck!

Pat

I live in Sri Lanka, and here the daytime temperature is about 85° F. It's a very sunny, dry climate. What are the most suitable flower bulbs to grow in my garden?

Salinda 

Dear Salinda,

I must say, I've never received a gardening question from Sri Lanka! It sounds like a beautiful place.

The problem with growing bulbs in a tropical setting is the weather. Most bulbs like a period of cold during their dormant season. That means they will likely bloom the first year you have them because they are growing and blooming on food stored in the bulb from the previous year. But production declines after that.

For example, here in California, tulips are practically impossible to keep going for more than a year or so without planting new bulbs because we just don't get enough cold weather.

From my research, I see that your climate is warm and dry, except during monsoon season, and without any cool weather. But I see that you can grow tea camellias. That said, I think there are some bulbs that might prosper for you.Some of the choices I am going to give you are actually corms or tubers, rather than true bulbs, but most people lump them all together.

If you can grow onions, chances are you can grow lilies (which are true bulbs). The Oriental lilies are fragrant, but usually come in shades of white or cream. The Asiatic varieties come in bright, vibrant colors, but aren't usually fragrant.

You might also try dahlias (a tuber like the potato). They love warm weather and come in many colors and sizes.

Other good possibilities: iris (a rhizome); crocosmia (a small, iris-like plant that will spread and makes brilliant orange flowers); watsonia (iris-like foliage with tall spikes of pink or white flowers);and amaryllis (spectacular flowers).

Also, paperwhite narcissus might work since they don't need a cooling period, but I'm not sure. They aren't an expensive plant, so it might not hurt to try.

I hope this helps. You might want to see what others you can find and try them. Sometimes plants will surprise you and do well even when the weather is against them!

Pat

I bought a home at a 3,400-foot elevation in Amador County. I have been blessed with a peach tree about 15 feet tall and a DBH (diameter at breast height) of 5 inches. Last summer, it produced about 50 wonderful peaches. I pruned it one-third back and now it's covered with golf-ball-sized fruit! I haven't seen any sign of peach leaf curl. Should I still spray the copper solution at the end of the year? Or am I safe?

You are too late to spray for curl this year, as you already know. The latest best time to spray (and the absolute best time to spray if you can spray only once) is at the pink bud stage—that is, when the flowers are showing color.

You would have leaf curl by now if you were going to get it. Keeping the old leaves cleaned up each year helps prevent the virus from spreading.

I find only the first flush of leaves gets the curl. A peach grower I once knew never sprayed, but picked off the affected leaves each year and disposed of them. The new leaves came out just fine.

If you want to spray next season, be sure to follow the directions as far as timing, but I used to spray only at pink bud and eventually quit spraying completely.

My suggestion is, the fewer chemicals, the better. Plus, it's one less task to do. Your task now is to thin the fruit. Pick away the smallest ones, then repeat.

My crepe myrtle and grapes have a powdery covering on the leaves. What is it and what can I do about it? Will it kill the plants?

It's powdery mildew, and my local nursery told me that in my area of the Northern California foothills, it is a dry-air mildew and that hosing off the leaves regularly would help.

It did: The parts of the plant where the sprinkler hit were free of the mildew. However, it is a fungal disease and can be controlled by a fungicide. You need to check at your local nursery and buy one that is designed for use on the plants that have the disease.

Sulphur is also used to control powdery mildew, and I have used that successfully, too. You can also use neem oil or jojoba oil, both of which are plant-based oils. Always follow label directions to the letter.

My impatiens are planted in the best location: plenty of filtered light, ample water, great soil and fed regularly. But all I get are leaves. What am I doing wrong?

I can tell you without asking any additional questions that the culprit is the fertilizer. Quit feeding them altogether or at least cut it back by two-thirds. The plants are getting too much good food and producing leaves instead of flowers. I guarantee this is the solution.

The winter squash plants have plenty of flowers, but I don't see any squash.

Squash, both summer and winter, first produce male flowers. Their job is to attract the bees that will be needed to move pollen from the male flowers to the female ones. Male flowers have a long stem. Female flowers have the baby squash at the base of the flower. If the flower gets pollinated, it will form a squash. So until the plant produces female flowers, you'll just have to wait.

See how Pat answered your questions earlier this year.