The most common reasons for plant failure occur in the first season due to lack of water, sunburn, and deer damage. Here are the most important points to remember when handling and planting nursery stock:
- Always protect nursery plants from drying out. Just because a plant is dormant and has no leaves does not mean it does not require moisture - always keep bare roots moist and protected from wind and sun, and keep container plants adequately moist and protected through the winter. Bare root plants can be kept for up to several weeks before planting by heeling them in –placing them in a shaded area and covering the roots with soil, potting mix, sand or sawdust to keep them moist. Protect bare roots from freezing. The trunk and branches can withstand colder temperatures than the exposed roots.
- If you are planting bare root stock it is best to plant your trees when fully dormant, before signs of bud break.
- Protect the bark on young trees from sunburn by facing the bud union North (away from the hot, southern sun) and whitewashing the trunk from the soil up to the first branches with a white, water-based latex paint that has been watered down, half water, half paint.
- Irrigate your tree - Lack of irrigation is one of the most common causes of failure. Full sized, established fruit trees can be dry farmed, i.e. grown without supplemental irrigation, on most sites in the Northcoast/ Mid Klamath, but all nursery stock will require irrigation the first several years in order to thrive and get through our hot summers. The best strategy is to install a drip irrigation system and lay down a thick sheet mulch to suppress weeds and conserve moisture.
- Protect young trees from deer - Deer are another leading cause of failure in our area. Fruit trees are just tender, young salad for a deer, and unprotected trees will not survive repeated browsing - plant your orchard inside a fence or install a fence around each tree.
Care Before Planting Realize that all bareroot stock, though dormant, is also in a state of shock. They have been dug up from the field with an inevitable loss of roots, and need special care even before planting. The most important thing to remember is KEEP THE ROOTS MOIST, even for brief periods, i.e. while transporting them to the planting site. When planting on a sunny day you can protect the roots with damp burlap or an old sheet. Do not leave bare root plants under a tarp in the sun, as heat will build up and kill the finer roots. If you have not pre dug the holes for your trees and must keep them for more than a few days, they should be HEELED IN (buried in a moist medium), in a shady spot and watered thoroughly. Keep the roots packed in sand, soil, peat moss, potting mix or aged sawdust (avoid fresh sawdust or wood shavings as they may contain compounds that inhibit root formation). Trees can be kept like this for several weeks if necessary, but should always be permanently planted before showing any signs of bud swell or growth. Protect trees from freezing before planting. Prior to planting, SOAK TREES IN WATER FOR 12 TO 24 HOURS. This will afford them a good long drink to compensate for any moisture loss in storage and shipping.
Site Selection You should have this covered already in your design and layout process, but pay attention while you're planting. Each plant has specific needs such as drainage, soil type, soil fertility, exposure and moisture. Generally, a moderately fertile and well-drained site is best. Do some research to find out the requirements of your plants (see references below). When choosing a site, pay attention to microclimates. Cold air, which may cause damaging spring frosts, drains away from slopes and ridges, making them good sites for planting. Planting near a south-facing wall can help late fruits to ripen in colder climates. On the other hand, trees such as Apricots, which are susceptible to early blooming, sometimes benefit from a colder site, say on a north side of a building, to keep them from blooming too early and losing their blossoms to winter rains. After choosing the site and spacing desired, lay out the orchard by putting 5 foot stakes at each tree location to line up and visually determine the planting sites. Remember that pollenizers, when required, should be within 50 feet of each other, the closer the better. Some trees, such as filberts and walnuts, are wind pollinated, so consider prevailing winds when planting.
Digging the Hole All that's absolutely necessary is to dig a hole large enough to accommodate the roots of the tree. However, the old adage is to dig a ten-dollar hole for a one-dollar tree. (Tip – if your ground is very rocky, don't dig any more than is necessary to accommodate the roots or you won't have enough soil to fill your hole in.) When digging keep the topsoil and subsoil separate. Loosen the sides and the bottom of the hole. Note that the shovel may "glaze" the sides of the hole, especially in clay soils, leaving a hard, compact surface that is impenetrable to young roots. For this reason it is always advisable to fracture the sides of the hole when filling in.
Amendments in Hole – Placing too many goodies in the hole, such as manure or compost, can create an environment that the tree roots never venture out of. The best amendments are low bulk sources of minerals, such as bonemeal, soft rock phosphate, kelp meal and oyster shell flour. Mix these with the topsoil, to be placed in the bottom of the hole, where most active root growth will occur.
Pruning and Planting If your tree has a bud union, face it north, or on the opposite side of strong prevailing winds. Carefully note where the soil line was on the plant so that you can plant it at the same depth as it was grown, or slightly deeper. With grafted trees it is important that the graft union be 3"-6" above the soil. Prune off any damaged roots just above the break, as well as crossing roots or unusually long roots. If there is a definite taproot (typical of nuts) leave this longer than the side roots. Remember that the tree lost several roots when dug, and this must be balanced by top pruning, so that the roots can support the canopy without strain. Trees under 4 feet are usually cut back to a 3 foot single "whip", cutting back any side branches and about a third of the top. Be sure to leave a healthy, plump bud at the top of the tree, cutting 1/4 inch above it. A rule of thumb: branched trees and multi-stem shrubs should have 50% of each twig pruned off. (NOTE – Pomegranates have a lot of fine branches, which must be thinned, otherwise the tree dries out in the spring.)
When ready for planting, put about 1/3 of the topsoil mix in the hole and place the tree in, spreading the roots. Often a mound of soil at the bottom is useful for keeping the roots spread out. Avoid placing any weeds or green plant material in the hole – they emit methane gas when decomposing, which does not agree with young roots. Put the rest of the topsoil in and tamp lightly. It is important to eliminate air pockets and ensure that the roots are in good contact with the soil. This can be achieved by puddling the tree roots with large quantities of water. Fill the hole and let it soak in, gently wiggling the tree and poking the mud with a stick to eliminate air bubbles. After the water has soaked in, fill the rest of the hole with the subsoil and tamp it firmly with your feet, keeping the stem upright.
Care of Young Trees Proper care is essential during the first few years of a tree's life, with the first season being the most crucial. A healthy soil and vigorous growth is the best insurance against pests and diseases. Be sure you weed and irrigate regularly during the summer, at least 1" of water per week (drip works great). Note that standard and semi-standard trees can usually be weaned to dry farming as they mature, but supplemental water is necessary to get them established. Top dress in the spring with compost or aged manure at the dripline. In any place with strong summer sun it is absolutely necessary to PROTECT THE BARK FROM SUNBURN using whitewash (white, water based, latex paint diluted half and half with water, painted up to the first branches) or a plastic, expandable trunk guard. Sunburn is the number one reason for tree failure in hot, interior sites.