Q: Wildflower meadows are so lovely, and we have a suitable area to have one. What advice can you give us?
A: The idea of a wildflower meadow is very fashionable right now, and they certainly are very attractive. However, you can't just go out and throw wildflower seeds among the knapweed and dandelions and expect to get a beauty spot. Here are some suggestions for getting a real wildflower bed instead of getting a new selection of weeds.
The hardest part is getting started. You really do have to get rid of the weeds, and that means either spraying with an herbicide and starting again or covering the area for one whole season and planting next year. Whatever you do, do not turn over any soil or do any tilling after you have killed the weeds. Tilling will just turn up millions of weed seeds, so make any soil preparations before you kill the existing growth.
Plant the seed as you would grass seed. A lot of seeds will be very tiny, and in order to get an even distribution you might want to mix the seed with dry sand or fine sawdust, or you might sprinkle the seed from the blade of a trowel. Walking over the newly seeded area as you go will help to make good soil contact between the seeds and the moist dirt. You could use some organic mulch immediately after planting and you will need to water frequently until the seeds are up.
For the first year, the weeds you thought were gone won't be and they'll grow faster than your flowers. The easiest way to deal with them is to mow the area when the weeds are about 6 inches high and before any of the weeds have made seeds. Leave everything you've cut off in place as mulch. You'll be glad to know you shouldn't get out there and pull weeds because you'd be killing your flower babies, which are still very tiny.
By the second year you should have to mow only once or twice when weeds reach 12 inches; it's OK to pull a few giant knapweed that year, as long as it's done only when the soil is moist.
By the third year, you'll have to control grasses that are moving in. The easiest way to do that is to burn in the spring just before the wildflowers start to grow. Or, at the same time of year, mow the grasses clear to the ground and rake out the clippings.
In succeeding years, you'll have to burn or mow every spring and possibly do some selective weeding. You'll occasionally need to add more flower seeds.
Q: I have a lot of vinca that is several years old and has always been healthy. However, this year some of it is turning yellow. What could be the problem?
A: From the context of this telephone conversation, we learned that the yellowing plants were in places with gravelly soil, and we feel sure the problem is just lack of water.
When the soil finally starts warming up in spring, sandy and gravelly soil can dry very, very quickly, especially if it's in the sun and more so if it gets wind.
Soil texture can change very quickly from one small area to another, so if you want to know what your soil texture is like in a particular area, here is an easy way to do it.
Dig up about two cups of soil that runs from the surface down about 6 inches. That's the area in which most plant roots will be. Put your sample in a quart jar, fill it with water, cover it, shake it up and let is stand for 24 hours.
When you look at the layers in the jar, you'll see that sand and gravel will be in the bottom, silt in the middle and clay on top. Any organic matter will be floating. That will tell you whether you have sand, clay or loam in that spot. Loam has ideal drainage, sandy soil will drain very fast, and clay will drain slowly, making it waterlogged.
If that soil is compacted, it can destroy the drainage and the soil's ability to hold water. Therefore, compacted soil, no matter what the texture, always needs loosening.
To learn what your drainage is like without considering the soil type, pick a spot where the soil is moist, dig a hole 4 inches deep and big enough to hold a 46-ounce juice can with the top and bottom removed. Put the can in the hole, firm the soil around the can and fill it with water. Then watch to see what happens to the water.
With ideal soil drainage, the water will drop 2 inches an hour. If it drops less than an inch an hour you either need to improve the drainage or plant only marsh-type plants in that area. If it drops more than 4 inches an hour, you need to add a lot of organic matter to help hold the moisture. You'll also need to mulch the plants in that area and probably irrigate more often.
With the opposite problem from yours, where there is clay soil that doesn't drain well, the easiest solution is raised beds.
Master gardeners Molly Hackett and Georgianna Taylor, whose motto is "Never trust a gardener with clean fingernails," welcome your questions. Send them to: 191 Eastside Highway, Hamilton, MT 59840; call 961-4614; or e-mail firstname.lastname@example.org.