It's hard to believe that we've already reached the half-way point in the gardening season. This is a great time to sit back, smell the roses and enjoy the beauty and bounty of our gardens. But we can't rest on our laurels too long. There's still a lot to be accomplished before gardening activities wind down for the year. Here's a rundown of mid-summer chores.
Water when necessary
We've had a fairly wet summer so far, but because many of our landscape and garden plants are shallow-rooted they need regular moisture throughout the growing season. Water if we don't get regular rain.
Watering takes on added importance as the weather becomes hotter and drier. When plants are repeatedly stressed for moisture, they just don't grow well. Flowering will be reduced, and the blooms that do develop may not achieve their potential. Without adequate water, lawns grow thinner, which allows drought-tolerant weeds to invade and take over, and vegetables may fill out poorly, be more susceptible to diseases or develop a stronger, more bitter flavor.
Because plants often run out of steam right about now, give your gardens a boost with some additional fertilizer. Work a small amount of granular vegetable fertilizer into the soil in large circles around tomatoes and other big plants and to the sides of row crops. (You could also use leftover phosphorus-containing lawn fertilizer very sparingly for this purpose, providing it contains no weed-killer or insecticide.)
Because flowers are typically planted in clusters rather than rows, it's easier to use a liquid fertilizer applied from a sprinkling can or special applicator that fits on the end of your hose. And pay special attention to flowers growing in containers; they need to be fertilized every two or three weeks, all summer long.
Do a garden audit
Assess your flower garden while it's at its peak and look for areas that could use some help. Then visit your favorite nursery or garden center and pick up a few container-grown perennials to fill the gaps. These plants are often on sale by now, but don't worry, there's still more than enough time for them to become established in your garden. Just water them regularly and add a layer of mulch to help insulate their roots. Many perennials will have bloomed already, but they'll bloom again next year -- unless you select a marginally hardy plant that may not make it through the winter!
Divide and conquer
Divide large established clumps of bearded iris if they look crowded and didn't bloom as well as usual. Lift the rhizomes without breaking their roots, then wash off the soil so you can see to cut out the old, woody centers. Trim leaf fans back to about 6 inches and replant each division so the rhizome sits somewhat horizontally, just below the soil surface. (Don't forget to incorporate a small amount of low-nitrogen garden fertilizer into the area before you plant.)
Continue to pick any ripe or over-ripe produce from your vegetable garden to keep plants fruitful.
When a section of your vegetable garden is no longer productive, don't let it go to weed. Instead, remove the plants, add a little fertilizer and plant a fast-growing leaf lettuce or spinach for early autumn salads.
If your soil is poor, a good alternative would be to seed clover, annual ryegrass or buckwheat as a "green manure" to improve the area for next year. Plant a thick stand to choke out weeds, then turn the plants into the soil once they start to bloom or become frost-damaged. This adds organic matter to the soil, along with a small amount of nutrients.
Time to prune
Prune foundation plantings of junipers, yews and arborvitae that have put on lots of new growth this summer. Even if you pruned in spring, it doesn't hurt to trim them again in mid-summer. If you do, the plants won't outgrow their location as quickly, nor will you be faced with the expense of replacing them as soon.
This is also your last opportunity this summer to prune potentilla and weigela and any other deciduous shrub you grow primarily for foliage rather than showy flowers. As we get closer to autumn, new growth triggered by pruning is less likely to harden off and make it through winter in good condition.