Coffee Grounds and Azalea


Posted by Horticulture Guy - Peter Punzi | Posted in Midwest U.S. Gardeners | Posted on 15-05-2012

Q. I tested the soil @ my Azalea: pH-7.0  Nitrogen- Low, no # given  Phos- High, no #  Pot- Medium, no # Coffee  Grounds suggested for pH and Nitro. correction. What who you suggest to correct ALL issues or where can I find out? Thanks for your Time and Assistance! I appreciate it! Monte Cardwell Wichita KS 67213

A.  Hello Monte – Coffee grounds probably won’t help lower the pH much unless you are dumping the coffee with the grounds.  But they will help some with Nitrogen and a good source of organic matter but t may not be sufficient if your readings are low.  If you are looking for fertilizer follow the lead of your soil test and go with a fertilizer that has a N-P-K ratio (those three numbers on the bags showing the percentage of each nutrient K being for potassium)of approximately 3-1-2. Or apply a nitrogen based fertilizer like urea or blood meal and a potash fertilizer like Muriate Of Potash. To adjust the pH I would use Sulfur soil amendment (azaleas would prefer a pH around 5.5)  – Alternately you could also try a chelated fertilizer like Miracid – which contrary to what you might think – does not lower the pH but protects the nutrients from being affected by a high pH (through chelation which comes from the Latin for claw).

Hope that helps – HG

Shady Cherry Laurel


Posted by Horticulture Guy - Peter Punzi | Posted in Southeast U.S. Gardeners | Posted on 29-10-2011

Q. While looking for a plant that would serve as a hedge (about 10′ tall) and grow in full shade, the garden center folks recommended the pruninus caroliniana. What I have read on the web says it needs partial to full sun. Will it grow in full shade? Kay – Charlotte, NC

A. Light requirements recommendations are always a bit shady (go ahead groan) to most people.  In part because there are different kinds of shade – early morning shade, afternoon shade, evening shade, dappled shade, full evergreen shade etc.  Plus you can look at references and see different recommendations in from different authorities. Some of this comes from the fact that shade in the southern latitudes is different than shade in the northern latitudes.  Prunus caroliniana is a native to NC (thus the specific epithet caroliniana) and is what is called a tree like shrub – and so will like to get large and could be trained as a large shrub or a small mutli trunked tree.  My resources indicate that it would be a full sun plant but could tolerate some shade.  One way to determine the amount of light your spot gets is to use a sunlight calculator.  If it reads anything less than partial sun I would suspect the shrub would languish.  If it reads partial shade then perhaps a Clethra alnifolia may work.

Vigorous Asian Pear


Posted by Horticulture Guy - Peter Punzi | Posted in Northwest U.S. Gardeners | Posted on 29-10-2011

Q. Hi Peter, we started a new orchard in the spring of 2009. Planted 5 asian pears, including a Mishirasu. The growth on that tree is ridiculous! I call it the octopus tree. The new shoots are over 3 feet long, and they are not growing up (like with the other asian pear varieties we planted) they flop over and eventually touch the ground.

We have pruned each winter. Should I do summer pruning with this tree instead next year? Should I not prune so much this winter? Not much on the internet about this variety, thanks!

Karen – Olympic Peninsula, WA

A. Hello Karen.  I have not grown this variety myself but it is typical to prune Asian Pears during the winter – but of course most pruning can be done at any time of the year if necessary. Pruning during the summer has a more of a dampening affect on tree growth than winter pruning does.  This is because the tree has invested energy in the leaves and doesn’t get to recoup it in the fall.  So I would suggest pruning as you normally  the tree as needed and not wait until winter on this variety.  You can still do your normal winter pruning but just add some summer pruning to keep this variety in check.  Better too vigorous than not vigorous enough!


A Clover By Any Other Name


Posted by Horticulture Guy - Peter Punzi | Posted in Gardening Q & A, Southeast U.S. Gardeners | Posted on 03-04-2011

Question: On my newly purchased property, I discovered clover with a dark, heart shape in the center of each leaf. I am having difficulty identifying what kind of clover it is. I am very interested to learn what type of clover it is. Thank you! Melinda – Tickflaw, LA

Mystery Clover

Answer: This does look like a clover – it reminds me of  a muted version of Black Four-Leaf Clover ‘Dark Dancer’ (Trifolium repens var. atropurpureum ‘Dark Dancer’).

Dark Dancer Clover

Dark Dancer Clover

But I don’t recall a cultiver with just a spot in the center.  My guess is either this is a cultiver from down south that I am not aware of, or it is a regression of that cultivar or variety that may have produced offspring that had less of a purple mark.  There is an outside chance that is is an Oxalis (which are sometimes confused with Trifolium) but the sure way to know would be to see it in bloom. Trifolium has a ball shaped flower cluster – oxalis has a single 5 petal flower.   If anyone reading this is familiar with this cultivar post a comment or send me an email. 

Wild Morning Glory Battle


Posted by Horticulture Guy - Peter Punzi | Posted in Gardening Q & A, Northwest U.S. Gardeners | Posted on 08-03-2011

Question: I live in Olympia WA, on black lake I have a doozey for you! I have been battling morning glory vine for nearly a decade. How do I get rid of this beastly vine. The root system is so broad and vigerous, it seems impervious to round up, vinegar, spectricide ect. I have tried to control it by plucking it as far down the vine I can dig, but seems like that just empowers it? Have even tried to eliminate light, still the beast lives. Any suggestions? Lisa Menge

Answer: Your are right Wild morningglory (Convolvulus arvensis) is a beast of a weed. The roots can penetrate down to 10 feet in some soils according to WSU extension. So once established it will develop an extensive root system that is a formidable oponent. It will spread by seed as well as from its root system that will persist year to year (perennial). Because of the extensiveness of the root system round up will only kill back so far and the remaining root system will re-sprout (it reportedly can do so from five feet below the soil surface!). Your plucking effort probably did not get nearly all of the root system. The vast root system not only can regenerate new shoots but is also a vast energy reserve which you must deplete over time. Most herbicides will only kill it back so far and then it will resprout from the remaining root system. So the plant must be continually starved and given no quarter. Continual diligence to prevent it from creating new above ground shoots is imperative. This will take time (I know you have been battling it for many years but the morning glory has been more persistent than you have). You said you have tried to eliminate light – but if it survives you were not successful. It must receive no light (like heavy black plastic mulch that overlaps and no holes for plants where they can peak through). So a combination of spraying or weeding any above ground growth regularly (no more than a few inches of growth should be allowed to form before they are removed). Just think if it doesn’t photosynthesize it will eventually deplete it’s energy reserves but it could take a few years of due diligence. Sorry no magic wand for this beastie.