Adrian Higgins
Washington Post Garden Editor
Tuesday, September 23, 2008
11:00 AM
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.
He was online Tuesday, September 23 to offer advice on lawns, flower beds, vegetable patches and window boxes.
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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washingtonpost.com: Order in the Courtyard (Washington Post Magazine, Sept. 21)
Adrian Higgins: Morning, we're here for the regular Tuesday chat but also to talk about my piece on a jewel of garden in Columbia Heights that was featured in the Sunday Magazine's Home and Design Issue on Sunday. I also have to make a sad announcement. Unfortunately next week's chat will be our last. This feature is being discontinued. I will continue to have a lot of gardening content on the website and perhaps next spring we can have a discussion group. But Tuesdays in the Park with Adrian is winding down.
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Edgewater, MD: Metropolitan Home had an article on how to construct a frame containing succulent plants that can hang on an outside wall. The plants are sprayed weekly with water for maintenance, and are supported in the frame by peat moss and cactus plant mix. Would our winter present any unusual problems for this plant presentation?
Adrian Higgins: This is a modification of the green roof principle, except engineers have worked out how to have green walls as well, which present more of a challenge in terms of water retention, I would think. But I'd love to see one.
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Indoor plant, DC: I'd like to find a nice indoor plant for a corner of my condo. Waist-height would be ideal. I don't have any outdoor space and it would be in partial light (underneath a window). I also travel at least one week a month, so something fairly low-maintenance would be great. Any ideas? Thanks!
Adrian Higgins: I am partial to Chinese evergreen and clivias.
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Capitol Hill - DC: We're considering planting a couple apple trees in our yard on the east end of the hill. Do you have any suggestions for city-tolerant varieties? Do we need to get 2 different varieties to ensure cross-pollination?
Thanks!
Adrian Higgins: Yes, some are self fertile but still produce more fruit with a cross pollinator. Some will need another tree to set fruit, it depends on the variety. I would highly recommend getting a variety that was developed for southern climates and is on dwarf rootstock. Look for one that is resistant to scab, rust and fireblight.
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Bethesda, MD: You've mentioned crimson clover in the last few chats. I have two grassy slopes that I'm tired of mowing, one gets morning sun and afternoon shade, and the other, the opposite. Would crimson clover be a good cover for these areas? If so, can I seed it now?
Adrian Higgins: No because it's a winter crop and will peter out next spring. I would consider a ground cover such as liriope, hypericum or daylilies. Or even landscape roses.
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Cheverly, MD: Hello, Adrian -
I have an 8' crape myrtle that was planted in Nov '06. During last summer's drought I belatedly realized I wasn't watering it enough (leaves looked wilted). However, it not only survived, it's thriving.
My question is, what are its water requirements now? I know we haven't had rain for a couple weeks now, is there still enough groundwater or should I water my tree? Is my tree considered an established tree, or is it still a new tree that needs to be coddled?
Thanks!
Adrian Higgins: Any new tree, including a dry lover like crape myrtle, needs extra water the first two autumns, when root growth is most active. Yours is probably out of the woods, no pun intended. I would still give it a light mulch now to conserve soil moisture this fall.
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Arlington, Va.: Professor, what soil amendments would you recommend to improve my chances of actually getting squash to grow next year? The plants all looked healthy at the start, but produced virtually no female flowers and then all shriveled up and died. Very disappointing! Any suggestions for what I can do now in preparation for next year? Thanks.
Adrian Higgins: I would make sure that there is a fair amount of clay in with your amended soil, and well mixed. This will give the even moisture that the vine needs. Mulch it with straw.
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Friendly MD: Thank you for taking my question!!
I know deer will eat almost anything but are irises a preferred delicacy or a food of last resort? I want to plant irises in our backyard where the deer like to roam.
Thanks so much!!!
Adrian Higgins: They will munch bearded iris, I think, but other iris species are more resistant, particularly Siberian iris and Iris spuria. I don't have deer, any advice from others out there?
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Arlington, Va.: The previous owner of my home planted black-eyed susans. Now that they are no longer blooming, should I cut the stalks down to the ground?
Adrian Higgins: Yes, and shake the seeds so they will germinate next spring.
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Anonymous: Good morning, and thanks in advance for taking my question. We have some bottle gentian and hardy begonia that I'd like to move because they're kind of overwhelmed by some taller plants around them. They're both blooming now, and I understand that the hardy begonia self-seeds, as opposed to being a true perennial, so I'm assuming I can just collect seeds in order to "move" it. Is that correct? What about the gentian?
Adrian Higgins: Hardy begonia spreads by underground tubers. It might self seed as well, but it's definitely a perennial and if you want to move the existing stand, or part of it, you can do so. Gentian is also a perennial, it doesn't like to be moved, but if you are careful about minimizing root damage, you can do that.
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Alexandria, Va.: Say it's not so! The end of the gardening chats? This is horrible!! I've learned so much from you and from these chats, and I'll miss them terribly when they're discontinued. Thank you for all the advice you've provided to the novice gardeners out there!
Adrian Higgins: Thank you. It has also been helpful to me, in knowing what sort of information people need in my columns. And I'm grateful for all the loyal community that has grown up around these chats.
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Moonflowers again: First, Adrian, I am extremely sorry to see you will no longer be available to dispense your invaluable advice.
I asked about moonflowers not flowering last week. I think I wasn't clear. The vines had been flowering as usual until about 3 weeks ago; now there are no blooms and no new buds forming. Last year they continued until first frost. Is there anything I can do to encourage the vines to resume producing buds?
Adrian Higgins: Thanks. Keep them evenly watered and remove any faded blooms. A shot of phosphate fertilizer might help. They usually do keep right on until frost, don't they?
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Rockville, MD: To fertilize or no? With the recent gap in rainfall I'm worried about burning the lawn. Should there be enough moisture in the ground to help the fertilizer along?
Adrian Higgins: You don't want to fertilize the lawn in a dry spell. We're not in a dire drought like last year, so you could soak your lawn a day or two before spreading fertilizer, and then soak is afterward. Also, make sure the feed you do get is slow release and that you apply it at the correct rate and keep it off paved surfaces to avoid nutrient entering the waterways.
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Alexandria, VA: I'd like some pretty and preferably flowering plants for my condo balcony. The problem is that I'm on the 16th floor, and it's always breezy if not windy up there (with a north-west exposure). Do you have any suggestions for what would do well under those conditions?
Adrian Higgins: I would select succulents and other rock garden plants that are suited to desiccating conditions.
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Montgomery County: I can't believe this chat is being discontinued! I will miss it so much...
Adrian Higgins: All good things come to an end, I suppose.
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Falls Church, Va.: Several of our front and side yard plants seem to have a faint white film on them, including our hydrangea and our lilac. Is this my imagination, or could something be infesting them?
Adrian Higgins: This is powdery mildew. Both these plants are prone to it and it is common in late season dry spells. You could spray preventatively with a baking soda solution, if you want to do that.
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Severna Park, MD : Good morning! I enjoyed your article about figs, I never thought that was something we could grow around here. I don't have a lot of room but would like to plant one, is there are variety that is small or that can be trained to fit a smaller space? Thanks!
washingtonpost.com: Fig Lovers, Rejoice. Your Time Has Come. (Washington Post, Sept. 18)
Adrian Higgins: You could grow any variety in a pot, I think it would be fun to grow one that is less hardy, such as Conadria, keep it in a large freeze resistant pot that you could either take into an unheated shelter in winter, or sink into the ground and mulch for the winter months. Restricting the roots will diminish the top growth.
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Washington, DC: So sad to hear the chats are winding down; I've always found them to be both useful and entertaining.
Another sad note is that the two magazine-quality hanging baskets I so carefully tended since May, and had grown to five feet in length, were stolen last week. Next year I'm putting some hidden cacti in the baskets!
Adrian Higgins: I think people who steal plants should be placed in a stockade and be forced to listen to bad poetry.
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Bethesda, MD: Adrian,
Help please! Someone gave me some Lamb's Ear to plant, it's in a brown paper bag at the moment. Is now a good time to plant this and if so where? Fun sun or shade.
Thanks and love this chat.
Adrian Higgins: Sun or partial shade in a well drained bed. Hurry, it doesn't belong in a bag.
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Reston, Va: I live in a very small, generic townhouse. I want to plant a few things in front of the house to brighten it up, preferably with very low maintenance.
Are there any resources where I can get some design ideas, tailored to our weather conditions?
Thanks
Adrian Higgins: Green Spring Gardens in Alexandria has some demonstration townhouse gardens. Meadowlark Botanical Garden in Vienna might be another source of inspiration.
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Falls Church: I would like to reseed my front yard. I think I have every kind of grass growing now. Most of it is still green. I have full grown trees in the back yard and I will be raking (front and back) when the leaves start falling. So how should I add grass seed so I don't rake up new grass? I love the trees; I doubt I had my AC on more than a month this summer.
Thanks
Adrian Higgins: As I've said before, lawns and trees don't really mix for lots of reasons. It would be better for your trees to convert the root zone into a bed of low growing ground covers, being careful to minimize root damage.
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Washington, DC: What a shame to lose this wonderful chat. I have learned so much from reading it! Is there someone at the Post that I can contact to let my feelings be known?
washingtonpost.com: You are welcome to e-mail me at elizabeth.terry AT wpni.com and I will pass on all messages to our editors. And do watch for information on a gardening discussion group, which will allow you all to get advice from Adrian and share tips with each other. - Elizabeth
Adrian Higgins: Thanks Elizabeth, (my wonderful producer).
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Flowering Perennials: I have lovely flowering perennials - lilies, phlox, baby's breath - in my garden. Last winter, I did not trim them down, and they all returned this year - as beautiful as last summer. What risks are there to leaving them alone again as this season comes to an end?
Adrian Higgins: We only cut back the top growth for our sake, not the plant. I tend to leave the dead growth of perennials well into winter, because it can be quite decorative with a white frost or rime on it. And the seeds persist for the animals. Leaving the old growth also extends an extra measure of hardiness to cold sensitive perennials such as agastache, penstemons and gaura.
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Mobile, AL: Dear Adrian, What fall plants, perennial preferably, do you suggest for a subdivision entrance? Approximate area 40x20 half circle. Plants under 48" in height. Mobile, AL Zone 8.
Adrian Higgins: Gosh, I would go to Bellingrath Gardens and get some ideas. Lots of ornamental grasses, I would think, and maybe some Louisiana irises.
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Franconia, Virginia: I lost most of my tomatoes and early veggie growth this year to an aggressive assortment of squirrels, chipmunks,woodchucks and deer. Any tips on advanced planning for next year to avert another disaster? I do plan to get a dog (previously I had a tomato loving mutt but at least he didn't take all of them)!
Adrian Higgins: Fencing, including buried hardware cloth extending out from the fence to prevent burrowing.
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Watering old trees?: We just had some drainage problems in our back yard taken care of, and the grass around several big red and Norway maples there is quite dry and brown. We treasure the trees for the shade and privacy from the house behind us; should we give them extra water, and if so how and how much? The trees are original (50-yr-old) plantings.
Adrian Higgins: Once established, both these trees would only need extra water in periods of extended drought. The Norway maple, I should say, while once popular is now considered an invasive weed. It also casts so much dense shade that growing anything around it is tricky.
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Silver Spring, MD: This is a gross problem and I hope you can help. I have a typically-small suburban back yard that is well landscaped with bushes and trees around the perimeter. I love my back yard. I also have a male dog. On some days, and here is the terrible part, there is a strong and unmistakable scent of dog urine. It is sometimes so strong that it's quite impossible to even contemplate having dinner on the patio, something I love to do this time of year. I've tried spreading lime around the areas he uses, but it doesn't seem to help. Do you have any suggestions other than not allowing the dog to pee in the backyard (impossible)? Typically, I add mulch to the gardens in the fall - would removing and replacing the mulch, rather than just adding new, help?
Adrian Higgins: You would have to keep watering the area. Male dogs pee to mark territory and if you have him fixed, you will find that problem much diminished.
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Washington, D.C.: Hi Adrian -- I have a very small patch of dirt next to my patio, and I'd like to plant a couple of varieties of bulbs there (including tulips, which I love). I'd like to choose bulbs that will bloom at different times so I have flowers for the longest possible time. Do you have any suggestions? Thanks very much.
Adrian Higgins: Just get a bulb catalogue. Scheepers, Van Engelen, whomever, you will find a vast array of early, mid and late season tulips.
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Suburbs, Maryland: I have a slope of bare dirt. What ground cover can I put down that will root quickly? Are there such things as roll-out sheets of ground cover, similar to what I've seen that is embedded with grass seed or seeds for flowers? I'd like to get something on there before nasty fall and winter weather. Thanks!
Adrian Higgins: These rolls of plants are a dud in my view. What I would do is take either landscape cloth or burlap, peg it to the hill with landscape staples, and then plant your ground cover through it, but cutting an X. You can try to hide the cover with a shredded mulch that should knit together.
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Washington DC: What? You're leaving us? What will we do? Who will make my black-tinted thumb slightly greener? Can we appeal to anyone?
We'll miss you...
washingtonpost.com: See above for my contact information... and be assured, Adrian's great advice will still be found in his columns, videos, and in the discussion group we plan to start by the time the spring gardening season gets underway. - Elizabeth
Adrian Higgins: Thanks.
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Silver Spring: I had some surprise dahlias this year. I had planted them in one place and the squirrels dug them up and put them somewhere else. Do I need to take them out for the winter or leave them be? Thanks so much for all your great advice.
Adrian Higgins: I would lift them after the top growth has been frost blackened. Store the tubers in bags filled with peat moss, and start them in pots in April and set them out in May. Burying them deeply should help deter the squirrels next year.
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Alex., VA: I patched some bare spots in my lawn this spring (we had to remove some trees), and over the hot dry summer, they burned and died.
Can I patch in the fall? Any tips or techniques to take advantage of?
Adrian Higgins: Seed now.
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Arlington, VA: Adrian,
What fall/winter crop vegetables can I plant now?
Thanks!
Adrian Higgins: Glad you asked, this is the topic of our latest episode in Community Plotlines, which will appear online on Thursday. Actually posted Wednesday night.
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West Falls Church: I recently purchased two plants and need to know how much sun they need as I'm getting different information.
1. Dwarf Alberta Spruce 2. Garnet Japanese Maple
Adrian Higgins: Both prefer some partial shade.
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Annapolis, MD: Good Morning, Professor,
I've had some slow but steady success growing a small thyme around stepping stones. Until now, that is. A lot of the green appears to have died, leaving large patches of brown stems without leaves. I believe the stems are dead, but I haven't checked to be sure.
Got any thoughts as to what could be going on and how to stop/fix it?
BTW, you suggested a camellia a couple years ago for a spot with morning sun. I took the suggestion and couldn't be happier. Many thanks!
Adrian Higgins: The usually culprit with thyme is crown rot from excessive moisture. I wonder if you should try another type of thyme, or, if it's heavy soil in shade, a ground cover named mazus.
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Rose in Alexandria: Thanks so much for recommending a Charles de Mills rose for us in last week's chat. I looked it up online and it looks lovely. A follow up question - is it ok to order a shrub like that online? I know that you can get bulbs and seeds online. Or should I try to call local nurseries to see if they have it? The only nursery I know in the area is Merrifield. Are there others to try? Or reputable online sites?
Adrian Higgins: You will be hard pressed to find that rose anywhere other than specialty rose nurseries. I would suggest Pickerings, or the Antique Rose Emporium in Texas.
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Ashburn, Va: When overseeding a lawn, is it ok to lay down fertilizer and seed at the same time?
Adrian Higgins: Well, the seed companies suggest a starter fertilizer, but maybe that's because they sell fertilizer. I think if you amend the lawn with rotted compost or the like, there will be enough nutrient to sustain the seedlings. Watering is more important.
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West Falls Church: I've got 3 Bradford Pear trees on my small yard. They're about 20 ft. high. Should I scalp them after the leaves fall, or chop them down outright?
Adrian Higgins: Don't scalp them. You will induce a lot of suckering growth next year. I would cut them down before they get much bigger and the costs for doing so will be prohibitive.
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Rockville, MD: I bought two cantaloupe plants and they grew all over my garden with loads of fruit. All of a sudden the fruit and most of the plant died. I didn't know exactly when the fruit was ripe. Did I just let it go too long before picking it?
Adrian Higgins: It may have succumbed to a bacterial wilt or a pest call the squash vine borer. You can tell when a cantaloupe is ripe by looking at the skin between the netting. When that turns yellow, the fruit is ripe.
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Salt Lake City, UTAH: Fennel. We need to move it. Is now the time? Thank you.
Adrian Higgins: It usually seeds itself. You could move it now, though.
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Omaha, NE: My husband and I just moved into house with a very developed yard. Several owners ago, it was a masterpiece with a lot of variety and plants blooming throughout the year...now it's just a wild, overgrown mess. We are not skilled gardeners (though we want to learn!) and we're overwhelmed at how to take back the yard and make it "ours." Any suggestions for how/where to begin? (Also, bulbs: we know we should be getting them into the ground now, but beyond that we're at a loss, any tips for beginners? Thanks!)
Adrian Higgins: It's important to look at the big picture and understand that what you need to do now is take out overgrown shrubbery and even trees, and devise replacements that will add vegetative structure to the garden in the next five to 10 years. That is, new medium to large shrubs that will be in scale and yet provide a skeleton for the garden. Don't be constrained by the current bed layout, you are free to enlarge or shift those beds. Don't focus on bulbs or perennials or annuals, you need to think about the structure of the spaces.
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Pittsburgh, PA: Good morning!
I am going to have a tree moved. It's been so dry here that the earth is cracked. Assuming that it will eventually rain, how late can this happen, or should I wait until spring for the great transplantation?
I'm going to miss these chats.
Thank you.
Adrian Higgins: Woody plants, mostly, are better moved now.
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Rockville, MD: When should I seed my lawn for grass? Is there any prep work I need to do (I have a lot of weeds and crab grass, plus a bunch of bare spots). Thanks!
Adrian Higgins: If your lawn is mostly weeds, you should renovate the whole area by renting a tiller and cultivating the soil, removing the weeds, adding amended soil, filling holes, etc. and then seed. You have until mid October to do this. A friend of mine used to top dress the seed with sand. This not only provided the constant moisture the seeds need to germinate and grow, it utterly confused the birds.
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Newport RI: So sorry that the chats will end... Is there hope for the future? Will spring come again?
Adrian Higgins: Spring will come again. Check out Thursday's Home section for a piece on coleus, and do see our new video of the Glover Park Community Garden. I'll be back here next Tuesday.
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