Five things to do in the garden this week:
Fruit. Consider growing blackberries and raspberries on trellises. They should be protected from our dry summer heat and perform best planted up against an east (or even north) facing fence or block wall with good ambient light. They demand a well-drained soil that should be cultivated to a depth of one foot or more prior to planting. Work in a 4-inch layer of compost or peat moss. Although blackberries and raspberries will produce with a minimum of fertilizer and water, they will yield significantly greater crops when minerals and moisture are in abundance. Mulching is highly recommended. A large variety of blackberries and raspberries can be ordered bare-root at a cost of $20-$25 per plant from Stark Bro’s (starkbros.com). Planting bare-root specimens is far easier than planting from containers. Furthermore, bare-root specimens will establish more quickly since their roots are splayed out when planting and can easily find their way. The bulky root balls of containerized stock may need to be loosened up or their roots may be circling the container and will have to be pulled apart and straightened prior to planting.
Vegetables. Unlike common potatoes, whose shoots grow from eyes, sweet potato shoots sprout from the end of the tuber. Sweet potatoes belong to the morning glory family as opposed to regular potatoes that are members of the nightshade family. Cut a sweet potato in half and place the two pieces in a pot of soil, cut side down, leaving the ends uncovered or balance each half potato on the rim of a jar or glass of water with toothpicks as you would an avocado seed that you wish to germinate. Eventually, you will see slips (shoots) reach 6 inches in length, a good size for planting. When detached from the tuber, some slips may have roots and some not. Those with roots attached may be planted in the garden while those without roots can be rooted in a glass of water prior to planting. Plant slips 12-18 inches apart in full sun (covering shoots with upside down plastic pots for the first week for acclimation purposes) and you will have large tubers in the ground sometime this summer or fall. There is no vegetable more nutritious than sweet potato and it is among the easiest and most reliable crops to grow as long as you make sure that the plants stay hydrated. Sweet potato leaves are edible, too.
Herbs. There are probably a hundred different scented geranium species and varieties, if not more. Their flowers in pale pink or white are an afterthought to the plethora of scents – peppermint, lemon, chocolate, nutmeg, apple, ginger, apricot, attar of roses, and cinnamon, among others – that their leaves transmit upon being rubbed or crushed. The chemical compounds that create these scents also impart a significant measure of drought tolerance. Moreover, they are easily propagated from four- to six-inch terminal shoot cuttings. My favorite among them is peppermint geranium (Pelargonium tomentosum). It may be the most undervalued ground cover for our part of the world. Once established, it’s quite drought tolerant. Its peppermint fragrance is stronger than that of the peppermint (Mentha x piperita) that is commonly grown in herb gardens. Its four-inch floppy leaves are blanketed with soft hair; their scent, size, odd shape, and fuzzy texture make them highly attractive to kids.
Perennials. I never cease to marvel at those plants that look fresh and clean despite a minimum amount of water, if any, needed for their care. One of these is bear’s breeches (Acanthus mollis), probably the lushest plant you will ever see with gigantic leaves having deep, precisely cut margins. Occasionally, you will come upon an abandoned house where the lawn is dead and watering of any kind has obviously not been done for years. Yet against the shaded, north-facing facade of this empty house, bear’s breeches will be growing in lush profusion. Bear’s breeches are indigenous to North Africa and southern Europe. This habitat implies drought tolerance, which bear’s breeches possess to a considerable degree. In fact, it would be fair to say that few plants for the shade garden are more drought tolerant than bear’s breeches. Bear’s breeches do tend to wilt in the summer if denied irrigation, but they never die from lack of water and return to the height of glory with winter’s first rain. These plants are perennially sustained by thick rhizomes which help them spread. Flower spikes make some sort of statement, I suppose, but I actually think the plants look better without them since the flowers detract from the unmatched majesty of the leaves.
This is your last chance to prune ornamental trees and shrubs that bloom on so-called new wood that will grow this spring. If you want a more compact bloomer, you can be more radical in how much old wood you remove from these plants. Plants that bloom on new wood include roses, crepe myrtles (Lagerstroemia indica), butterfly bushes (Buddleia spp.),rose of Sharon (Hibiscus syriacus), panicle hydrangea (Hydrangea paniculata), and Abelia spp. By contrast, late winter and spring bloomers must not be pruned now because doing so would put a damper on their flower show. These include azalea, Viburnum spp., oak leaf hydrangea (Hydrangea quercifolia), lilac (Syringa vulgaris), Cotoneaster spp., and mock orange (Pittosporum tobira).