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Something eating my Abutilon!

Dear Garden Guru,

My abutilon has some sort of pest. The leaves have several holes (all over the place not concentrated in center or edges). Most of the leaves are affected. I have an abutilon right next to the one with the problem and it is unaffected (though a slightly different variety of abutilon). Thoughts on what to do?

David in San Francisco

Hi David,

Sounds like Slug or Snail damage. The best way to be sure is to check at nighttime, as most leaf eating pests are nocturnal. Slugs tend to like moist shady spots, which we assume is where your Abutilon is located.

The solution is to try picking off and discarding any you see, and using Sluggo snail and slug control to eliminate the ones that come out of hiding. This is a non-toxic product that is safe to use around pets. Slugs usually die within 4 to 6 days after eating it. Sluggo lasts about 3 to 4 weeks and then breaks down as an Iron fertilizer. Reapply as needed.

Brugmansia

Dear Garden Guru,

I have had a Brugmansia Charles Grimaldi for at least 7 years and have had numerous problems with it such as aphids, snails. etc. I have told myself that I am not giving up on the plant, but it has never flowered. Is there such a thing as a male and female tree and do you think that I am missing one of those? Help!

Julie in San Francisco

Hi Julie,

Brugmansia are very much dependent on daylight to trigger blooming. They will start to set buds when  the days start becoming shorter and nights become cooler, usually late August to September.  Also Brumansia stalks must become forked before they produce flowers. Growth below the fork is juvenile or vegetative.  Growth above the fork is considered adult or flowering.  Have you cut the plant back so that there is no fork?  Are all the stems and trunks on the plant still straight?  The plant does not require male and female.

Aphids on succulents: help!

Dear Garden Guru,

What is the best way to get rid of aphids from my succulents? They are only damaging a couple varieties but the ones damaged are pretty bad. Thanks

Hunter in San Francisco

Hi Hunter,

You can control the aphids with Bonide All Seasons Oil. This non-toxic oil spray will smother both eggs and adults. Water your plants prior to spraying and apply when temperatures are 75 degrees or less.  Thank you for choosing to garden with us!

Lemon and herb recommendations for a SF Mission garden

Dear Garden Guru,

We live in the sunny but windy Mission district. Can you recommend a lemon tree and herbs that will work in this micro-climate? Thank you!

Donna in San Francisco

Hi Donna,

The Meyer lemon does very well in San Francisco.  The Eureka lemon will also grow but gives only one crop a year where the Meyer is known to produce almost year-round.  Herbs that will do in your neighborhood are rosemary, oregano, marjoram, thyme, and sage. These are woody plants and are not thirsty.  You can grow parsley, chervil, and savory but these “soft” herbs will require more water.

When should I start planting?

Dear Garden Guru,

Recently I moved from San Bruno to San Carlos. When is the ideal time to plant my garden seedlings? I wonder if it too early to start my garden (particularly tomatoes)?

Mara in San Carlos

Hi Mara,

You can start your gardening projects right now. This would include planting your seedling vegetables (peas, greens, strawberries, cabbages, kales, beets, carrots, onions, spinach), as well as the tomatoes, beans and squashes and basil. All Sloat Garden Centers now have the most varied vegetable selection of the season. As you plant during this cool spring weather, please keep in mind that tomatoes need consistent warmth. If you want to plant tomatoes now, you will need to protect them from cold nights.

Growing salad greens

Dear Garden Guru,

I'd like to know the best way to grow salad greens throughout the summer. Can I plant them in succession so that I'll have 4 months of salad? Also, I live in a foggy pocket of the east bay - does that make a difference?

Beth in El Cerrito

Hi Beth,

The easiest way to get your summer greens going is to start with pre started cell or jumbo packs. You can always supplement with a sowing of seed.

Should you opt for seeding only, be sure that you do not bury the seeds too
deeply. The best results with lettuces and greens is to prepare the bed (be
sure to mix in Loam Builder and Agricultural lime) so the soil is nice and crumbly. Sprinkle the seeds on top of the soil and then water. The seeds will settle into the soil at the right depth. Carrots and Lettuces need UV light to germinate! You do not need to pull up whole heads, it is better to cut the plants off about an inch above the soil. The greens will quickly regrow. Feed with a liquid fertilizer such as Maxsea All Purpose after cutting. Should you want to pull up whole heads or the plants begin to slow down coming back, you can resow or plant every 3-4 weeks to keep a fresh crop coming. The fact that you live in a cool, foggy location is actually a blessing for growing greens. They do not like it hot. We actually recommend planting in part shade in our hotter areas.

Tomato plants

Dear Garden Guru,

My tomato plants always look beautiful when I get them in the ground. I water and fertilize and then right after the plants flower they turn yellow and spindly and they don't fruit very well. What am I doing wrong?

Liz in San Bruno

Hi Liz,

Yellow and spindly tomatoes don’t fruit that well do they? Believe it or
not, I suspect that you are loving your plants too much. Over watering
tomatoes will wash away all the nutrients you so lovingly applied, it also
reduces needed oxygen in root zone and makes the plant susceptible to
disease. Your plants should be deep watered 2 to 3 times a week. If the
plant is seen wilting in the middle of the day, ignore it. Tomatoes will
close their stomas in the heat of the day to prevent water loss by
transpiration. They will perk right back up by late afternoon. If the plants
look droopy in the morning, they need water. Too shady a location will also
cause plants to be spindly but you usually see that effect immediately. If
the leaves are showing some signs of browning, your plants may have
Verticillium or Fusarium wilt. These are soil borne pathogens and there is
no chemical control available. Warm and humid conditions will hasten the
onset of wilt. It is highly recommended that you plant tomatoes labeled
with “VF” (Verticillium/Fusarium) on the label as these are resistant
varieties. Should there be an “N”, that means resistant to root knot
nematodes. Hope this helps for this year’s crop!

Planning an herb garden

Dear Garden Guru,

I am envisioning a small, kidney shaped herb garden right on our front lawn. I'm thinking about a raised bed, nothing too complicated, probably borders of some kind of stone or hardscape. What sort of herbs grow best in our climate? And can you offer any process insight in design?

Eric in San Francisco

Hi Eric,

Herbs that do well in your area are: Rosemary, Spanish Lavender, sage, parsley, Santolina, chive, and marjoram or oregano. Thyme and basil can be fickle. You may want to reconsider the kidney bean shape. A square or rectangle is more conducive to the classic herb knot and easier to work with. Choose plants that contrast in foliage color. After the size of the bed is decided, graph paper and colored pencils are very helpful. Each square could represent 1/4 ‘ so consider planting two 3″ pots per foot. Use a different colored pencil for each herb. In other words, 4 squares in a row would be colored the same. It might be worth looking at some of the DIY and HGTV links or calling our Design Department to schedule a consultation. The number is 388-3754.

Patio lemon and herb garden

Dear Garden Guru,

As a chef, my edible garden is very important to me. I currently hold a SE exposed patio in SOMA with good light in the absence of fog. I grow many herbs and a dwarf Meyer lemon tree. My lemon tree shows slightly yellowing leaves. I'm guessing lack of nitrogen and other trace minerals? Also the tree is producing several new flowers and buds. I'm worried the small tree cannot produce or support too many whole sized, ripe fruits. Shall I prune and reduce the crop size? One more quick question pertaining to the other herbs. Any recommendation to increase the crop and longevity of the delicate herbs? Cheers.

Dave in San Francisco

Hi Dave,

It is common for Citrus trees to yellow up in the winter. It is safe to feed them, even in the winter, as a green, well fed tree is actually better at surviving extremes of weather. We like the Growmore Citrus Growers blend which contains all the trace elements Citrus need. You can supplement with the EB Stone Citrus Food to provide more nitrogen. Citrus are notorious for producing more fruits than they possibly could support. The plant will thin itself when the young fruit is the size of green peas. There is no need to prune other than to shape.
As for the herbs, you may want to plant more of what you use most. I am thinking you mean things like Basil, parsley, chive, and thyme. Basil, by nature, peters out in winter unless you are growing it in a greenhouse. Thyme, being a woody shrublet, tends to pout in the winter. To encourage herbs to resprout more quickly after a pruning, feed them with a liquid fertilizer 1/2 strength every time you harvest. I like to plant herbs in 3′s. I rotate the harvest among them and it ensures I have enough when I need it.

Growing peas

Dear Garden Guru,

When is the best time to plant Sweet Pea starts? When are they for sale in garden centers? Thanks.

Lisa in Novato

Hi Lisa,

Alas, the best time to start sweet peas in your climate is in October. Planted in the fall, they develop strong root systems and then take off in the spring. Both seeds and starts are available. The second best time is in February. Our stores will have jumbo packs of tall growing sweet peas available in straight colors. Shorter Knee High varieties will be available as mixes. Our store in Novato regularly stocks them each spring but feel free to place a special order so that they will obtain them as early as possible for you.