Over the Garden Gate: Questions from the garden center

With many gardeners chomping at the bit to get their annual plants and vegetables into the ground, there is an endless supply of questions from those visiting local greenhouses, nurseries and box stores.

Some gardeners rely on "wait until Memorial Day," while others use Mother's Day as a signal to begin planting. Of course, if one is planting perennials, shrubs or trees, they can be planted as soon as the ground thaws (which it was a while ago). As I continue my part-time nursery sales associate job at a local farm and greenhouse, I continue to get lots of questions on when to plant as well as some of the more frequent questions included here.

Grab your garden trowel and let's dig in!

Dear Doug – My kids got me the prettiest hanging basket this year for Mother's Day as they do each year. Last year, however, most of the plants died prematurely. What can I do to prolong the life of my plants and keep my beautiful basket beautiful longer? Signed, Long live my hanging basket.

Dear Long live – The first thing to determine is whether you have a sun-loving or shade-loving basket. Most baskets include information on the sales tag attached to the basket. A sun basket will thrive in a location that provides at least six hours of direct sunlight daily, while a shade basket is looking for no more than three to four hours of direct sunlight each day.

Secondly, watering is critical. Due to the limited size of the basket, along with the fact that most potting mixes do not readily retain moisture, your basket may dry out quickly, especially if it is a sun-loving basket. Probe your potting mix with a finger to a depth of approximately 1 inch; if your finger is moist, no need to water. If your finger comes back dry, water thoroughly until water runs out of your basket's drain holes. During hot sunny days, your basket may need to be watered twice per day.

Lastly, do not forget to feed your basket with a high-quality fertilizer. A complete fertilizer will include macronutrients nitrogen (for leafy top growth and greening), phosphorus (for roots and flowering) and potassium (for disease resistance, cold hardiness, and general durability). For your flowering baskets, select a fertilizer that has a higher concentration of phosphorus (the middle number on the container will be the highest). Normally, fertilizing every seven to 10 days will keep your hanging basket thriving throughout the growing season. And, oh, yes ― deadheading, or removing spent blooms, will result in more proficient blooming for many types of flowering baskets!

Hey Doug – During my spring plant shopping, I have noticed an increase in the number of native plants being sold especially at local nurseries. Should I expect better performance from native plants over those I have traditionally selected over the years? Signed, Confused.

Dear Confused – The short answer is YES. Native plants are those that grew here before European settlers arrived. Those that are native to our region are used to our environmental conditions (yes, even the clay!). Native plants improve wildlife habitat and conserve our regional plant diversity. Many bees, birds and other pollinators rely specifically on natives and in many cases, do not benefit from the planting of non-native plants. You will be doing yourself and nature a big favor by planting natives. If you would like to attract pollinators to your garden, plant several of the same native plants close to each other. This will give the pollinators a bigger target when they are seeking pollen and nectar.

Dear Doug – Several years ago I planted a lovely hydrangea in front of my house. It grew and flowered for the first year or two, but now it has stopped flowering and appears to be dying. I just found the tag for my hydrangea which says "part shade," but I planted it in a location that gets lots of afternoon sun. Did I doom my plant by not planting it in the right location? Signed, Distraught.

Dear Distraught – While it's hard to know for certain without seeing photos of the plant's damage, it sounds to me that you may very well have diagnosed your hydrangea problem. A gardener's mantra should always be "right plant, right place." While some hydrangeas thrive in full sun (at least six hours of direct sunlight daily), many need some protection to avoid being scorched. "Part shade" is defined as between four to six hours of direct sunlight daily, but that should be morning or late afternoon sun. Plants that like part shade generally need to be protected from the hotter, more intense afternoon sun. Plants labeled "part sun" also need between four and six hours of direct sunlight, but part of this time can be in the hotter, brighter afternoon sun, which may actually aid their leaf development and flowering. My suggestion is to transplant your hydrangea into a part shade location before giving up on it. Good luck!

Dear Doug – I just finished planting my perennial garden, and since I’m a neat freak, I want to top it off with some nice-looking mulch to add the finishing touch. My next-door neighbor uses small white river rocks around his plants and has them piled up around his tree trunks. Is river rock a good mulch, and if so, why does he stack it against his tree trunks? – Signed, Neat & Tidy.

Dear Neat & Tidy – One of the basic reasons for mulching is to suppress weed growth in your garden. Unless your neighbor has placed landscape cloth under his rocks, weeds will soon grow between the rocks which will be difficult to eradicate and will detract from the beauty of his garden. Even with landscape cloth, weeds will still appear.

Good organic mulches are the best choice for mulch because these will contribute nutrients and microorganisms; rocks will not. Examples of organic mulches include shredded leaves, compost, well-rotted manure, pine needles, or some combination of these. According to the Penn State Extension Master Gardener Manual, compost is the gold standard for mulching perennial beds. The most abundant and commercially available mulch is shredded or chunked bark mulch ― probably the image you think of when hearing the word "mulch!" Such mulch can inhibit the growth and spread of perennials in the garden and should be avoided unless other organic mulches cannot be obtained.

Stacking rocks or any mulch for that matter, against tree trunks, shrubs or stems of perennials should be avoided ― period! Some landscapers and homeowners incorrectly pile mulch against tree trunks and stems of shrubs and perennials for appearance (in the Master Gardener program we call this "volcano mulching!) This practice can damage new foliage causing it to rot, and it gives insects a protected area in which to attack the plant. Keep the mulch at least 3 to 4 inches away from the trunk.

Properly mulching your perennial garden with at least 2 to 3 inches of mulch will suppress weed growth and maintain moisture during the growing season, and will also add a layer of protection for plants during the winter. Mulching is one of the best steps you can take for your garden, just be sure to not overdo it!

Well, readers, that's all from the garden center for today. Contact the Master Gardener Hotline of Beaver County at [email protected] for dependable, research-based answers to any of your gardening questions. Monitor the upcoming weather forecasts to determine when it will be best for you to get those veggies into the ground. Once the likelihood of overnight frost or freezing has passed, grab your garden trowel, and dig in! Happy Gardening!

Doug Canan is a Penn State Extension Master Gardener in Beaver County.