Hi Angie, I’m in zone 6 I have some questions here! 1. My neighbor has pine trees along his fence, so I have their needles all over that side. Would they poison the soils and crops in those area? I’m thinking about having a raised bed in that area for edible vegetables. 2. Is it true that pine needles will kill any plants under them? 3. I’m not sure how to get rid of the grass in the area I want to make the raised bed. Can I put a plastic sheet over the grass for a week to kill it, throw in the soil? Or do I really need to remove the grass? 4. The north side of my foundation bed is empty and I’m planning to put josee lilac and mock orange there. Is it okay to plant them close to the house? Do you have any fragrant plants or evergreen (nonstinky please) to suggest for the north side of the house? 5. The south of my house (this side is along the street) has some peonies, but once they die down the garden looks empty. What would be good to plant in that area? 6. Where can I get soil at a good price? It’s sad that I spend more on soil than the plants!
The Gardener’s Answer
Hello, Cath in Kentucky: Pine needles are not harmful to plant material; if anything they may acidify the soil over time but some garden centers sell pine straw bales as a mulching option. Before constructing your beds, keep in mind that vegetables require full sun so make sure you have a space that will receive a minimum of six hours of direct sunlight. The dimensions of your raised beds are going to be up to you and the space limitations you are working with. The most important dimension is the depth. Ideally you do not want it to be any less than a foot deep and in direct contact with the existing soil. This allows enough space for the roots to spread and continue into the earth if needed. This is especially true if you intend to grow any root vegetables. Growing in raised beds certainly has its advantages, one of the most important being that we can create the ideal soil mixture for our plants. A mixture of quality topsoil, compost, and manure provides plants with the optimal environment in which to grow. Soil structure, fertility, drainage, and pH are all important aspects in creating this environment. It can be expensive if you are trying to fill a raised bed so you may want to think about buying in bulk. First you will want to till up the base soil and then add topsoil, compost, and decomposed manure. Different layers of soil can create barriers, not allowing soil to penetrate, so make sure to mix it all together. Equal parts topsoil and amendments would be best, but heavier on the topsoil is fine as well. You also want to avoid working the soil if it is too wet because of compaction issues, which can lead to lack of oxygen movement. As for getting rid of the grass, removing it is ideal but killing it with plastic, layers of newspaper, or cardboard is effective as well. After the grass is removed/killed it is best to till the soil before adding any additional soil or amendment. You may want to consider planting the lilac and mock orange on the south side of your home since both of these plants are sun lovers. They will not receive as much sun on the north side of your home as they will on the south side. Evergreen options for the north side include: aucuba, pieris, mahonia, taxus, and evergreen azaleas. You always want to make sure each plant has enough room to reach its mature size before putting it in the ground. Read each grower’s tag carefully and take into consideration both height and width. Companion plants for peonies will depend on the space you are dealing with but all sun-loving perennials, ground covers, and shrubs, such as amsonia, echinacea, asters, or even ornamental grass could all be nice options since they will give you color at different times of the season. I would suggest taking measurements of your space and then visit your local garden center to see what catches your eye.