Ask-a-Gardener: Your Gardening Questions AnsweredBy Melody Rose (melody)
April 20, 2013
bgthumb25 asks: I'm getting pots or bags for my vegetables this year.I'm curious on what gallon size would work good on them. Spinach,radicchio,baby choi,baby romaine,beefsteak tomato,TX sweet onion & cucumbers(bush & pickler).I hear the larger the better.I was thinking 2,3,or 5 gallon.Any larger & I probably couldn't afford the soil needed to fill each.Would 3 gallon be fine for all?
Angela Carson answers: The size of the pot varies considerably with the type of vegetable you are growing. Many salad greens, such as the spinach, radicchio, and lettuces, need only a shallow depth of soil, as they don't have extensive root systems to support. They can be grown in containers as shallow as 6-8 inches, such as those designed to sit on windowsills or as window boxes. Onions, too, only need soil about double the depth of the final bulb size, perhaps 12-15" in depth. If you do choose to plant these in larger pots, you can add gravel or a thick layer of leaves or compost to the bottom of the pot before adding the soil to cut down on the amount of potting soil needed. Tomatoes and cucumbers, however, need considerably more soil to support the top growth of the plant. The size of container for those depends somewhat on what variety of tomato or cucumber you are growing. Some dwarf or patio plants may fare well in a 3 gallon pot, but most full-sized tomato plants will do better in a 5 gallon pot. To encourage formation of a strong root system, it is best to plant your tomato seedling very deeply, burying the stem almost up to the lowest set of branches. A 5 gallon pot gives you considerably more room to plant the seedling deep, and also provides more weight from the additional soil to prevent tipping over. Tomatoes can get quite top-heavy, making them susceptible to tipping during high winds. When you are choosing a tomato plant for your pot, check the label carefully. Determinate tomatoes, as a general rule, don't grow as tall as indeterminate varieties, and are more appropriate to container growing. Cucumbers are vining plants, and will likely need some sort of trellis or support if grown in a pot. Again, check the size of the mature plant when selecting your seedlings. Keep in mind that most leafy greens do better in cooler weather, and benefit from some shade during the hotter months, while tomatoes and cucumbers need warmer weather and full sun to thrive. If you had intended to grow them together in the same pots, you might find that their differing sun requirements make it difficult to keep both types of plants happy. Also keep in mind that shallower pots dry out more quickly, while deeper pots hold the moisture a little better. Self-watering pots, with a water reservoir at the bottom, allow you a little more leeway in how frequently you need to water. You'll find that tomatoes and cucumbers are both heavy drinkers, and will need daily watering. The addition of moisture absorbing crystals may help, though you have to be careful not to let the soil dry out completely if you use them. There is some risk that the moisture crystals will begin to draw moisture from the roots themselves if the soil becomes bone dry. I often add a layer of mulch to the top of my large pots, to help retain the soil moisture.
mindyk37asks: A collection of iris roots were dug up and left in an open bag since the winter of 2011, placed outdoors in a shed, and lost track of. They were my Aunt's and my Nana's before that. My Aunt developed pancreatic cancer and we lost her this January. I've just found the bag of iris roots. They are dry as bone. I've put them in a large draining pot outside, covered them with peat moss and saturated them with water. I thought I should kind of soak them for a week and then put them in a normal flower bed, partially exposed. Any chance they'll make it?
Jill Nicolas answers: I'm so sorry you lost your aunt to cancer, and I understand your wanting to save these irises if at all possible. The good news is that bearded irises are fantastically tough. People have tossed old rhizomes (tubers) over a fence and found them sprouting the next spring. As long as they haven't dried up to nothing, some should still be viable. Your instinct to soak them was good, but I wouldn't leave them in the wet peat as long as a week. Even with dried out rhizomes, rot is usually more of a risk than lack of moisture. Soak them a few hours or overnight in a bucket of water (maybe with a little bleach or hydrogen peroxide), and they will probably plump up quite a bit. Plant them out just as you would normally (see my DG article, "Planting Iris 101" You could try potting up a few also, as it's easier to provide good drainage in pots. Leaves may not appear for some time, but as long as the rhizome is visible there's hope for it. Flowers may take another year or two, but be patient, and hopefully you'll have a beautiful stand of bearded irises to enjoy and share -- a living memorial to your aunt & your grandmother.
hopelee9101 asks: Hi all just wanting to get some advice. I have a chain link fence that borders the road and want to plant something that grows fast, preferably stays green all year, possibly flowers and provides privacy. Easy, right? Well I can't seem to think of anything. I live in zone 8b, area is full sun until about 5 in the evening and the soil is clay and stay moist. Would welcome any and all suggestions.
Sally G Miller answers: That's a challenge as you found out; there are many beautiful, non-evergreen, climbing vines. Some common evergreen vines climb well on trees or walls but do not twine on a fence. I did not immediately have a suggestion for you, but I think I can help. Carolina Jessamine or Jasmine, sometimes called woodbine, is described as evergreen. It is a vigorously growing vine that will flower with scented, trumpet shaped, yellow blooms. Comments from several DG subscribers who have this vine say that it is fully evergreen in zones even colder than yours. Sounds like a winner! This link will let you read comments from others who have the vine. One even specifically says how well it works on a chain link fence.
Jill Nicolas adds: Good for you changing an eyesore into a gardening opportunity! Another possibility is Coral Honeysuckle, Lonicera sempervirens. This isn't the invasive Japanese one, but is still a fairly vigorous vine. It is pretty much evergreen for me in zone 6/7, even putting out an occasional midwinter bloom, so I'll bet it would be evergreen for you. While your evergreen perennial vines are getting established, you can fill in with fast growing annuals like Hops to get some screening this summer. I would not recommend morning glories (Ipomoea purpurea) or the Black-Eyed Susan Vine (Thunbergia alata) as they are aggressive reseeders in my zone and downright invasive in yours.
Melody Rose adds: The image at the left is Carolina Jasmine growing on a chain link fence. The link in PlantFiles will take you to the listing for this plant where you can view many other images of it growing on fences.
Image courtesy of member 'Floridian'
petrouchka asks: I live in Pahoa on the Big Island, Hawaii and would like to know if I can grow cherry trees. I would love to have the spring flush of cherry blossoms but don't know if they can handle the amount of rain that I get at my house (180-200"/yr). The drainage is great, have a lot of sun. Don't know what they like. Thanks for your help.
Melody Rose answers: Cherry trees are some of the most beautiful of the flowering fruit trees. Unfortunately, it isn't the rain that is going to be a problem. Cherry trees are members of the stone fruit family and they require a certian amount of cold temperatures in order to set blossoms. In frost-free areas, there just isn't enough winter weather to set the tree's inner clock in motion. They think it is always summer. You might look for an alternative pink flowering tree that is happy in tropical conditions. The Cassia javanica might be a good choice. It blooms in late spring and early summer. One of our PlantFiles reports indicates they do well in Hawaii and the County Building in Hilo, has them planted around it.
Question # 5
bkosegi asks: I have a small area where I had planted few sedum.Every year I have to dig old roots out that came from a shrub that was removed years ago.Is there anything easy that I might use to stop these from growing?I rent so I am stuck with this problem.
Melody Rose answers: We all have this problem on occasion. When we take a shrub or tree out in our established gardens, the roots are always an issue. I have the same situation in my front garden bed right now. I took a redbud tree down that was struggling, and now the roots have sprouted 'suckers' everywhere. The bed is planted with perennials and I'd need a backhoe and a whole weekend to set things right. What I'm doing is clipping the sprouts as soon as they emerge. Every couple of days I'll go around the bed and snip off any redbud shoots poking through the mulch. The roots have stored nuitrients, but sooner or later, the lack of any top growth will cause them to die and break down. The tree (or shrub in your case) needs top growth for photosynthesis. Without it, the plant will eventually die. Any chemicals that you could pour on the roots would have an effect on the other plants nearby, so I really can't advise that. It is pretty much a war of wills and I plan to patiently out wait the roots. I hope this helps, if anything, at least there's misery in company, right?
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