Garden almanac, Garden Pests

In the Garden this Week

In the garden this week: as it gets hotter, water your newly planted trees and shrubs more remembering they need more water than watering your lawn will give. For the first year or two most of the roots are contained in the root ball of the container they were in. I planted a crabapple tree a couple of weeks ago and have watered it every three days. Stick your finger in the root area and if dry water.

Drought injury on maple leaves
Drought injury on maple leaves

The spots appearing on apple and pear trees are apple rust. They are roundish reddish-brown lesions going through the leaf. There is not much that can be done now, and apple rust does not harm older trees.

Apple rust on apple leaves
Apple rust on a pear leaf

There is a lot of herbicide drift still showing up on tomatoes and peppers being very susceptible to 2,4-D injury. Most herbicide shows up as deforming (curled) leaf growth. Roundup usually shows up as a browning of the leaf area or brown spots. Aphids will curl leaves but look closely and you will see the aphids in the curling portion of the leaf.

Herbicide injury on a tomato plant
2,4-D injury in a tomato plant
Roundup injury in a tomato plant
Roundup injury in a tomato plant

If you have a good apple crop you might want to think about spraying the apple maggot. I have not seen any yet, but when you have them, it is too late. So, if you have had damage from the maggot, spray with an all-purpose orchard spray every 10 days until mid-August (follow label instructions). Online there are apple maggot sicky traps you can hang in the tree.

Apple maggot fly
Apple maggot fly
Apple maggot in an apple

Do not water in the heat of the day for lawns, flowerbeds, and gardens. Not only do you waste money, but it can also harm some plants. Wait till early morning.

Garden almanac, Garden Pests

Aphids are Becoming a Problem this Week

Aphids on a tomato leaf

Aphids are becoming a problem this week. If the plants (vegetables or flowers) are becoming deformed, look underneath the leaf and see if you have tiny green, black, or reddish “bugs”. If so, use Neem oil or insecticide soap to kill them. Be sure you get the undersides of the leaves to rid yourselves of these tiny pests. Sometimes they cause witch’s broom in some shrubs like cotoneaster and honeysuckle, which looks like distorted growth on the tips of the branches. On ornamentals, you can use a systemic insecticide.

Picture of a young grasshopper nymph
Common Field Grasshopper (Chorthippus brunneus) 2nd instar nymph

If the rains (few and far between) have not killed the little grasshoppers (nymphs), you may have a problem. The small they are the easier they are to kill. In the flowerbed or garden use Seven. Grasshopper baits around the perimeter of these areas help. Keep the weeds and grass around the garden mowed. It gives me great pleasure seeing the mowing and chopping of these insects up!

Cabbage looper eating a leaf

Cabbage butterflies are out in abundance which will lay eggs on the Cole crops, then the eggs hatch into little green caterpillars which can wipe out the crop. Used Sevin on a schedule to control them. Better yet is a product called Bt (Bacillus thuringiensis) which is a biological chemical killing young worms without harm to the environment. I have not found this product around the area, however, it can be ordered through any online garden store. These worms are hard to see being the same color as the vegetable, so most likely you will see the holes and damage first.

Blossom end rot on tomatoes

Blossom end rot is showing up in tomatoes and peppers as a large leathery brown spot on the bottom of the fruit. The problem is a calcium (and magnesium) tie-up in the soil due to dry and warm conditions. To prevent this use a mulch and keep your watering even.

Skin cracking of a tomato

Another water problem is the cracking of the tomato fruit usually along the top and shoulders. The cause is water going to the fruit faster than the skin can compensate for it. Again, even watering and mulch help. Some varieties are more susceptible to this condition like the cherry tomatoes and varieties like Early Girl with thinner skins. As the summer goes on this condition should decrease unless we get a heavy summer rain.

Purslane "weed."

A few questions about purslane showing up in gardens and flowerbeds. Do not use any herbicides this time of year. Pull and remove it because they will root down again if left in contact with the soil. Better yet, use it as a garnish with any salad you make. They were grown and used as food at one time. You can buy cultivars as blooming plants in the greenhouses in yellows and reds.

Garden almanac, Garden Pests

This Week in the Garden

This week in the garden. There have been questions about why my vine crops like cucumbers and summer squash are blooming but not setting fruit. Vine crops have male and female flowers and only the female flower produces fruit after being pollinated. The first flush of flowers is usually male then followed by female flowers. If you look at the flower, the female flower has a little fruit behind the blossom and the male flowers have a straight stem connected to the vine.

Some of the fruits may have a rotting end on the fruit. Most likely this is caused by improper fertilization, particularly in vine crops. This should cure itself in time.

Now let’s talk about cross-pollination between like a pumpkin and a cucumber. The answer is no. The plants have to be in the same Genus to cross-pollinate. For instance, different varieties of cucumbers will pollinate together as will squash. I planted yellow and green zucchini and got a few striped fruits, which was still good. Some varieties of melons will cross-pollinate among varieties. The odd fruit will show especially if you save the seeds from the fruit and plant the seeds next year or if a volunteer plant germinates and grows producing the odd fruit. That is why you buy new seeds every year or use up what is left from last year.

If your grass tips turn brown after mowing, this is most likely due to a dull or chipped mower blade. Sometimes mowing during the heat of the day causes the cut tip to dry out quickly.

Black spots on rose leaves is a fungus that spreads rapidly among certain varieties of roses. Use an ornamental fungicide to protect against the spread of this fungus. There are rose varieties resistant to this fungus.

Iron chlorosis is showing on some shrubs and trees. Some varieties show yellowing leaves with green margins. Our high soil pH sometimes ties up the iron (and magnesium) in our soils especially when the soil is dry. Treatment of liquid iron to the foliage or soil helps. Silver and Amur maples are particularly susceptible to this condition.

It is still not too late to plant or replace most vegetables in the garden due to hail or insect damage. Hopefully, we have at least 100 days till frost.