Got a chronic case of green thumb? Like getting your hands dirty? Adrian Higgins, garden editor for The Post's Home section, is here to help. Higgins is a firm believer in "tough plants for tough times" -- the varieties that combine good looks with stiff resistance to disease and pests. He currently rules over a garden filled with spring bulbs, daffodils, ornamental onions, perennials, asters, yarrows, hostas and day lilies. Higgins, an avid organic gardener who believes chemicals are a last resort, also tends his own herb and vegetable gardens where he grows peas, garlic, onions, lettuce, rhubarbs, radishes, carrots and more.

Higgins was online on Tuesday, April 8 to offer advice on springtime gardening.

A transcript follows.

Catch up on previous transcripts of The Garden Plot.

Higgins is the author of two books, "The Secret Gardens of Georgetown: Behind the Walls of Washington's Most Historic Neighborhood" and "The Washington Post Garden Book: The Ultimate Guide to Gardening in Greater Washington and the Mid-Atlantic Region."

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Chapel Hill, N.C.: Garden mystery: we have a plant thief and cannot figure out the culprit. Over the past couple of months, we have lost several plants and had others moved. A ranunculus suddenly disappeared a week or so after being planted from its 6" pot. It just disappeared--no soil disturbance or holes, the entire plant, roots and top, were simply gone. Same happened this week to a phlox. About 10 parsley plants have similarly disappeared over the last 6 months. Also, plants have been moved from their holes and left with intact roots in another place. A heuchera and small Siberian iris were found intact about 10-15 feet from the holes where each once grew. We have voles, moles, chipmunks, squirrels and deer (no evidence of rabbits), but I did not know that any of these ate entire plants and then smoothed the soil back. Have-a-heart traps have yielded only angry squirrels. We hope you can help solve the mystery and maybe suggest some solutions.

Thank you

Adrian Higgins: Voles will remove entire root systems but leave the doomed top growth. Rabbits and deer will remove the top growth and occasionally pull out entire plants. Squirrels will excavate and drag things around. Maybe they're all in league.

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Richmond, Va.: Why didn't you win a Pulitzer? No one asked me.

My other question is when will you be putting in annuals? I am always in a rush to get started but most of the time things kind of sit there until May.

Adrian Higgins: Ha ha. Cool season annuals such as pansies and snapdragons can be enjoyed now. In Richmond, start planting warm season by the end of April, beginning of May. There is little advantage in sticking in a heat loving thing like impatiens or sweet basil too early because they will sulk in the cool soil.

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Arlington, Virginia: Do lilac bushes need a lot of sunlight? I have a bush which is in the shade for most of the day that seems stunted, with some malformation on the leaves. Should it be moved, and if so, what's the best time of the year to do that?

Thanks so much.

Adrian Higgins: Yes, lilacs like sunlight, not just for bud formation but because that will position them in a place of more air circulation, which is important to reduce powdery mildew later in the year. Established lilacs are difficult to move.

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Charlottesville, Va.: Good morning, Adrian,

I have two dwarf (30") Alberta Spruce in pots flanking either side of our front door. Please tell me what I should do to keep them healthy.

(Thanks, too, for your always interesting and helpful columns.)

Adrian Higgins: The most important thing is to keep them out of the afternoon sun. In such a place, they become magnets for spruce mites, which will increase in huge numbers and turn the needles brown. They are now hatching, so it is also important to stay on top of them by washing them off with a spray of water. Horticultural oil would be even more effective.

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Woodbridge, Va. : Adrian - love your chats - submitting early due to a meeting. We planted 3 climbing roses last year - all still doing well. How do I care for them? Also, one has what I could call Rosehips, should I trim those or let them be?

Adrian Higgins: Most modern climbers are remontant, or reflowering, so trimming faded flowers will encourage reblooming. Old garden roses are not remontant and some are grown for the beauty of their hips, I think of Rosa moyesii Geranium, which is more ornamental in fruit than in flower.

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Lady's-mantle question: I love alchemilla and want a border of it, but I've gotten conflicting advice. The garden-center person told me to plant it in part shade, away from afternoon sun, but it's listed elsewhere as a full-sun plant. I'm in Ellicott City. What do you advise?

Adrian Higgins: It is not terribly happy in our hot, humid climates, so you should give it some protection from the afternoon sun.

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Alexandria, Va.: Good Morning -- May I ask if you could recommend some flowering plants for window boxes in a full sun, second story location which could handle watering just once a week? Daunting limitations, I concede, but I hope your expertise can solve this dilemma. My thanks! ... a faithful reader and fan, I very much enjoy the discussions.

Adrian Higgins: I think you would have to go with the palette of succulents used for green roofs, sedums, escheverias, etc.

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Arlington, Va.: It's our first spring in our new (old) house in Arlington. I'm planning on scheduling a county mulch delivery but not sure if I should order leaf mulch or hardwood mulch. Thoughts?

Adrian Higgins: I would go with the leaf mulch, which is not as attractive, but will break down faster and feed the soil quicker.

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Tuscaloosa, Ala.: re: Beer and Slugs from previous week. The first time I tried this the slugs came from miles around (looked like some bad movie -- Attack of the Killer Slugs From Outer Space!), but not ONE ended up dead in the beer; maybe they had designated driver. Tried repeatedly -- same result. I ended up using the beer to attract them onto a piece of cardboard, where I sprinkled them with salt and then just discarded the cardboard.

Adrian Higgins: Try some homemade, that might kill 'em. It did me once, or nearly.

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Washington, D.C.: Hi Professor Higgins!

My backyard is about 100 ft and rectangular with an ugly chain link fence surrounding it. The area gets full sun all day and I would like to cover the fence with a vine. Any suggestions?

I don't want anything that would be too invasive or self-seeding because I plan on planting a perennial flower border in front of the fence.

Am I shooting for too much here?

Thanks

Adrian Higgins: Campsis, maybe clematis armandii. Kiwi vine.

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Germantown, Md.: Hi Adrian,

We had a terrible mosquito problem last year. Our back yard is only about 20 x 20, but I couldn't go out at all after about July because the tiger mosquitoes were all over me, even with long sleeves and way too much bug spray. I've never experienced anything like it!

I have found no standing water in our yard but we're in a town house and our homes are connected - we have no control over what our neighbors are doing in their yards on the other side of the fence.

Is there anything we can do in our yard to minimize the mosquitoes? There is also a small deck (about 3x8) built against our fence and I think previous owners used to throw beer cans and garbage under there. I can't access underneath it at all. I worry that there may be water collecting in cans under there. I thought about pouring sand between the deck boards, but I don't know if that would be effective for filling anything under there.

Any suggestions or ideas? I don't want to be trapped inside for another summer!

Adrian Higgins: I think you have to somehow gain access to that area, that sounds like the source of the mozzies. Tiger mosquitoes can propagate in something as small as an upturned bottle top.

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Roanoke, Va.: Hello and here's a tree question for you. With a line of white pines that I want to thin, can I take out some of them or must they all go? I was told that if I remove only some of them, the remaining ones would have lost the support of the other trees and be likely to fall. Only one of the tree companies I talked with mentioned this, but a landscape person also told me this. Is this true? The background: I have a line of 40 white pines, about 40 years old. They were planted fairly close together, I presume to provide a screen between our house and a neighbor's. I wanted to "lighten up" this dark and heavy screen, and so I was going to thin out selected trees and group of trees. Some of them have fallen down on their own, although caused little damage since they are away from structures. So there is little safety need to do this, more an esthetic need. Your perspective would be appreciated!

Adrian Higgins: I don't know why they would fall, they have anchoring roots and are a pliable softwood. You might want to take out one or two at one end and see how the survivors respond. But if the limbs are interlocking, you will have to dismember the tree marked for removal with some care to avoid damage to the others. Don't seek to remove the stumps and roots of the fallen trees.

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Grass seed: I was at Strosniders this weekend - they ran out of grass seed, blaming it on their supplier who said they can't get enough because the farmers in Oregon are planting corn instead of growing grass seed as they can make more money off it with the ethanol debacle. My question is this - do you suggest a sun/shade mix and if so, what should I look for? I'm obviously going to shop around but I'd like to get the seed down this weekend (or do you think I'm too late?).

Thanks!

Adrian Higgins: Fine fescue is better suited to shade, but won't take a lot of foot traffic or nitrogen fertilizer. You can have a lawn in a shadier site, but you have to be prepared to renovate annually, and this is best done in September.

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Washington, DC: Adrian, hope you can help. I need a tough groundcover that can hold the soil in place at the base of a west-facing fence. Something that can take hot sun and occasionally drying out (I will water, but want something tough). I was thinking about Euonymus fortunei Kewensis. But now I'm thinking creeping thyme. Or maybe sedum. Thing is it's a 60 foot long fence so I need something that will fill in quickly and not break the bank. thanks!!

Adrian Higgins: Creeping thyme is too ephemeral in our climate. Sedum would be expensive. I might go with leadwort, sometimes called plumbago. It spreads by runners and will hold the bank together, after three or four years mind.

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Portulaca: for that weekly watering window box - And they come back!

Adrian Higgins: That might work, as would the hardy ice plant.

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Richmond, Va.: I am just beginning to compost. I have always left my grass clippings on the lawn after mowing. Is it better to rake them up and add to the compost pile or leave them on the lawn? Thanks!

Adrian Higgins: Lawn clippings are a valuable source of nitrogen, the caveat is that you have to stay on top of the grass as it grows this time of year so that you are not putting too much mass down. Once a week may not be enough over the next month, especially if it rains. Your compost should be a balance between brown and green matter, so I would add the clippings if you need them. But do integrate them into the pile, don't let them sit as layers or they will become like a couch potato, anaerobic and unpleasant and useless.

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Winchester, Va.: I just received a supposedly "hardy" gardenia that I ordered from a catalog. I'd like to plant it in a protected location, walled garden along a west-facing wall. However, since we have a wooded lot on a mountain, the gardenia will not get full sun. Is there any hope for success for an outdoor gardenia here? I dream of having the scent waft through the bedroom window ...

Adrian Higgins: I don't think even the hardy varieties will work in Winchester. I would plant it in a nice pot and be prepared to winter in a cool but protected location.

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Takoma Park: I recently bought a house in Takoma Park and am house rich, but cash poor (but not upside down!). What are some free or cheap resources for gardening information, plants, and maybe even design help for a new homeowner and gardener in the DC area?

Adrian Higgins: You could go to Brookside Gardens and see what grows well and looks good. There is no one quick easy place where you can learn to design and plant a garden in one fell swoop, short of plunking down $100,000 to a design build firm that will bring you an instant landscape, but no real knowledge that will carry you forth.

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Washington, D.C.: Thanks for taking my question.

I'd like to start a compost pile and wanted to know your thoughts. Can I include fruit and vegetable peelings? How large should the bin be for a 2 person household and what else should I include?

Happy Spring!

Adrian Higgins: You can keep a lidded bin in your kitchen for the scraps, but you will need something much larger and outdoors for the compost. As the scraps fill up, take them out to the pile, and bury them in the pile to discourage four legged marauders. If you have a problem with rodents, I would go with a plastic sealed compost bin.

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Indy, Ind.: Do you have any suggestions for a plant that would work well under a very drippy water spigot? Right now, we've got a bucket under the spigot to reduce water waste and keep that side of the yard from turning into a swamp, but I was wondering if some water-loving vegetative matter would work? It's in a part-sun area and gets LOTS of water when we're watering the veggie beds.

Adrian Higgins: Mint would love it. Obedient plant, perhaps.

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Pittsburgh, Pa.: What do you think about the products that contain iron phosphate for slug control? I have been using Escar-Go from Gardens Alive and the 5 inch slugs that we had the pleasure to step on at night have disappeared. It seems to work, but is there any downside to such a product?

Thank you.

Adrian Higgins: They're considered far more benign than the earlier poisons, which I would avoid because pets are drawn to the bait.

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Washington, D.C.: At our country home, the beds around the house and in woodland gardens have compacted leaves that were not raked in the fall. If I leave them, will they be useful as mulch? Can I top dress them with pine mulch to look better?

Adrian Higgins: Depends where they are, if they are in woodland, just leave them, but if they are in a conspicuous bed, I would rake them out, go over them with the lawn mower and either add them to the compost pile or put them back as a leaf mulch.

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Silver Spring... Trumpet Vine on fence?: Wouldn't trumpet vine eventually lift, pull and flatten even a chain-link fence (and then chew it up)??

I'd love to have Campsis, but simply haven't the telephone poles it takes to support it!

Does it also spread (like Wisteria) into the yard? Or is it a bit more mannered?

Adrian Higgins: There are dwarf varieties, sorry I can't find a reference to hand.

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D.C.: So far I am having lots of good luck with my potted phaleonopsis (orchid). However, I have noticed the roots of it are starting to pop out of the soil. I was always told to be careful about not putting it into too big of a pot but is this an indication it needs to be repotted? Should I put moss or something on top of the soil to protect the roots?

Adrian Higgins: It's telling you it should be repotted. Get fresh orchid mix. You can remove the old stuff by gently washing off the old material under a lukewarm stream of water.

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Falls Church: What's the best remedy against termites? Do you recommend switching from commonly found dark hardwood mulch to cedar? Are there any chemicals that can be purchased at the big box retailers, or commonly found home chemicals that can be used?

Adrian Higgins: I think removing sources of wood next to buildings, especially woodpiles. Yes, bark and cedar wood mulches are going to be less attractive than mere hardwood mulches. If you have them close to the house, I would get a pest control company to sort them out. They typically sink lures that then infest the nests.

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Annandale, Va.: HI Adrian,

I attempted to replace an overgrown area by our back fence (which is in a place difficult to water) with a wildflower meadow. Didn't work, ended up with lots of tall weeds.

I've gotten it cleared out but want to plant hardy perennials. I don't want to have to care for this part of yard. Any recommendations? It is about 150 square feet.

Adrian Higgins: I would go to Green Spring Gardens and see their perennial displays. You're talking about a fairly large area that is going to take a lot of planting (and weeding the first two or three years.)

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Lorton, Va.: I live in a the mid-section of a townhouse row that backs to another row of townhouses. Any suggestions on how to "create" a sense of privacy when there is none? I don't think evergreens will work and we have full sun exposure.

Adrian Higgins: I don't know why evergreen wouldn't work, the key is to pick plants that will not outgrow the space, and be patient, i.e. five years. Cherry laurels, yews, Japanese black pine, all these might work. The key is not to try and screen out all the neighbors but to create a garden of inward looking ornament and interest.

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Havre de Grace, Md.: Hi Adrian!

I see so many times you talk about plants that don't like "wet feet." Well, are there any plants that do like wet feet? There are areas of my yard where the water table seems to be at 3" (my dog dug a 5" hole and it has been a constant water source for her for the past month). Even once it stops raining so much, there are very wet areas around the yard. And it's flat. So are there any plants that would like this? In particular, there is one place (on the north side of the house) where I would love a prickly bush or vine along a fence line. If it were the south side and drier, I'd want a climbing rose.

Adrian Higgins: Roses won't take waterlogging but there are loads of shrubs and perennials native to riparian areas that will take it boggy, including some hollies, myrica, salix, and lysimachias.

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Barnstable, Mass.: I would like to plant a 20-ft long, seasonal wind screen (also privacy screen) between my house and its neighbor, but I don't have a lot of depth there. So privet -- which is a bit boring and a lot of work to keep clipped -- gets too big. What say you to a hedge of tall hydrangeas such as the beautiful "Unique"? And where does one fine a true "Unique" -- I hear they're often mislabeled?

Adrian Higgins: With good culture, hydrangeas might grow to six feet high, so you decide if that's enough. I don't know where you would source Unique, but there are loads of varieties available. Check out Judith King's website, http://www.hydrangeashydrangeas.com/

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Fairfax, Va.: Good Morning,

Last year I planted several Irish Yews along one side of my yard. (It is protected/shaded by larger conifers). One side of one of the yews seems to be not so healthy, and has extensive browning.

I would like to do additional plantings along this stretch of my yard, but I think it's unwise to plant only one species, as disease may spread more readily.

Could you suggest a companion for the yews with similar shape but perhaps faster growing rates that would work in these conditions? Is there anything I can do for the existing yew that looks unhealthy?

Thanks.

Adrian Higgins: That is a consideration. The biggest killer of yews is heavy wet soil. If they have good drainage, but decent soil, they are reliable for us.

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Pulaski, Virginia: What other shrubs would look good in a mixed border with Mohawk Viburnums? Thanks!

Adrian Higgins: Maybe deciduous azaleas?

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Bowie: I have never seen so many weeds on my yard this time of year as I do this year. Can I use Weed-b-gone this time of year?

I planted in some patches last year, but mostly no new grass.

Adrian Higgins: No the weeds you have now are winter beasties that are about to seed and then die, so spraying them with a herbicide won't do anything about the seed set. I would pull them and bag them.

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Richmond, Va.: Good morning Adrian! My house is on a corner lot and this spring I want to install a mixed shrub/small tree border to give the back yard some privacy from the road. The border (southeast side of house, 5-6 hours sun) would be anchored by two mature, pink crape myrtles -- I am thinking viburnums, sweetspire, maybe a dogwood, beautyberry? Can you offer some suggestions? Thank you!

Adrian Higgins: All of those would work, and if you have room, consider an Eastern redbud, now coming into glorious bloom.

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Washington, D.C.: Good morning! Can you suggest a trailing/spilling companion for my Japanese anemone? It's currently alone in a barrel-sized container in a fairly shady spot. I'd prefer a perennial, and if it's something that is somewhat evergreen here, that would be wonderful. It's a spot that could sorely use a bit of green in the winter.

Thanks for the chats!

Adrian Higgins: If you can keep it watered, I would consider a hakone grass. Otherwise, prostrate rosemary. We're outta time, folks. Look for us online here next week and in Thursday's Home section.

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