Category Archives: plant problems

Plant Problems- What’s a Gardener to do?

Just one of many banana slugs in my garden

Everything was growing nicely in the garden until the banana slugs and squirrels started eating me out of house and home, fungal leaf spots and aphids appeared and the gophers and deer decided they really liked my plants. What’s a gardener to do?

Troubleshooting is a form of problem solving. And whether it’s your car, your smart phone, an irrigation system or yellowing leaves on a plant the goal is to find the solution and make everything work again. When you eliminate the potential causes of the problem hopefully the solution restores everything to its working order. Sometimes this is easier said than done as we all know.

A few weeks ago I received a text with pictures of some plants with leaf spots and was asked for a solution. Over the winter we received a lot of rain so I wasn’t surprised. But if this were mid-summer I’d suspect that the plant leaves were burned by the sun and not getting deep enough irrigation. At this time of year, however, black or brown spots on leaves are fungal or bacterial problems and should be treated with an organic fungicide like Serenade which is non-toxic to bees and beneficial insects, Neem, copper or sulfur spray to prevent and control spreading. Affected leaves should be discarded.

The subject of how much fertilizer and what kind came up in another troubleshooting email. The issue was whether to use an organic high phosphate fertilizer in order to encourage bud development on a notoriously short-season tree dahlia. A single spring application of rock phosphate should be sufficient. Sometimes adding too much phosphorus can actually hurt a plant, preventing the uptake of other nutrients necessary to prevent other deficiencies. A balanced fertilizer containing all three nutrients- nitrogen, phosphorus and potassium-was recommended for the remainder of the season.

Winter yellow leaves on Meyer Improved lemon

Then there are the problems in my own garden. Well, it seems I am always trying to solve something with plants, pests or critters but now it’s the lemon tree. The older leaves of this tree are yellow. The new growth looks fine so it isn’t an iron deficiency where young leaves display green veins along with a yellowish color.

It isn’t a nitrogen deficiency either where the mature leaves slowly bleach to a mottled irregular green and yellow pattern, become entirely yellow and then are shed while the discoloration spreads to the younger leaves. I fertilized in March with an all-purpose balanced fertilizer. Citrus are heavy feeders and require a steady source of nitrogen, the ideal citrus fertilizer having a ration of 3:1:1 (N:P:K)

After eliminating other mineral deficiencies or overwatering as the problem I decided that my lemon was simply dropping interior leaves which is normal after winter but I wanted to trouble shoot all potential causes to be sure citrus greening wasn’t the culprit. If it had been this deadly disease the leaves would have exhibited an asymmetrical pattern.

To quote Sherlock Holmes “Once you eliminate the impossible, whatever remains, no matter how improbable, must be the truth.” I’ll try to remember that when I’m troubleshooting my next problem in the garden. Oh and by the way my banana slug relocation program is going well.

June in the Garden-What to Do?

I didn’t get everything done in May that I had on my to-do list. Who ever does? Anyone who tends a garden knows how fast plants grow with the longer, warmer days and nights. So this month I continue to work on my own garden tasks as well as help others renovate their gardens to look great, support native pollinators, wildlife and habitat.

If you battle dandelions and don’t want to use chemical weed killers around pets and children, get out the white vinegar from the cupboard. On a hot sunny day spray straight white vinegar directly on the weed. This method will kill whatever it touches so direct the spray carefully. If the dandelion is in the lawn, wait a week, pour some water on the dead spot to dilute any lasting effects of the vinegar. Then poke a bunch a holes and drop in some grass seed. Sprinkle a bit of fertilizer where the seed is planted and keep the area moist. In three weeks you won’t remember where the dead spot was and the dandelion will be long gone.

Many plants, both vegetable and ornamental, are bothered by aphids and other sucking insects as well as foliage and flower eating bugs. From cucumber beetles, flea beetles, stink bugs, weevils, curculios to borers, the list of trouble makers is endless. To help deter them mix up some pepper spray in your kitchen.
1 tablespoon hot pepper sauce or 1 teaspoon cayenne pepper
6 cloves garlic, crushed
1 quart warm tap water
Let stand I hour, strain and spray plants either in the morning or evening.

Pink rhododendron.

When the last flowers of your rhododendron, azalea, camellia, weigela and spirea have finished it’s time to prune them. If you prune too many months after flowering your risk removing the flower buds forming for next year. Basically it’s best to prune lightly each year to shape plants that have become too leggy. The rules apply to most plants. Prune to the next whorl or set of leaves. To increase rhododendron bloom next year, break off any faded flower trusses just above the growth buds being careful not to damage the new buds.

Swallowtail feeding on lemon

Apply the second fertilizer application for the year to your citrus and fruit trees. The final one for the season should be immediately after harvest. Apply the fertilizer to the soil around the drip line of the tree where feeder roots are located and scratch into the surface. Water in well. As with all fertilizers, make sure the trees are moist before you fertilize. Young trees in their first, second or third growing season should receive half the rate of established trees.

Another garden to-do this month includes summer pruning of wisteria. To increase flowering next spring and keep these vines under control cut new growth back to within 6″ of the main branch. If you want to extend the height or length of the vine, select some of the new streamer-like stems and tie them to a support in the direction you wish to train the plant.

Erysimum ‘Apricot Twist’

Another maintenance tip is to shear spring blooming perennials to keep them full and compact. Candytuft, phlox subulata, aubrieta and other low growing perennials benefit if you cut off spent bloom and an inch or two of growth. Other perennials and shrubs that benefit from the same treatment to keep them compact are erysimum, lavender and Pink breath of heaven.