I recently attended a talk given by Carol Allen at Behnke’s on this topic and wanted to pass her wisdom along.
Benefits of Containers/Raised Beds:
- You can garden where you get the best sun; if you plant in containers and it turns out your plants aren’t getting good sun, you can always move them
- Less weeding!
- You don’t have to bend over as far
- You can walk in between plants without compacting the soil they’re growing in, which is a big problem in traditional vegetable gardens
- Create an edible landscape; if you have an existing decorative garden, try integrating pretty vegetables, like rainbow chard, into the garden
- Not much in the way of edibles will grow without sun; if you’re gardening on a balcony that doesn’t get direct sun, try a community garden plot instead
- Get more space by going vertical with trellises or teepees; it means less bending over and produce that doesn’t touch the soggy, dirty ground
- Think about your space parameters and what you want to grow; for example, if your only sunny space is a concrete driveway and you want to put a shallow raised bed on it, it’s not going to be deep enough for anything but shallow-rooted veggies, like lettuce
- Always use mulch!
- Raised beds are nice for any vegetable garden (even if you have lots of space); you can make the soil optimal for growing veggies, you can divide and conquer (e.g. “I’ll just plant one today and do the other one tomorrow”) and all the veggies will be easy to reach without setting foot in the bed (never make a raised bed that’s wider than 4ft)
- You don’t need to pretreat the ground that the bed is going to sit on for weeds unless you have weeds with runners
- Don’t line the bed with landscape fabric; it just gathers sediment and retards drainage
- When constructing the sides, use pine, never pressure treated lumber or pallet wood because they’ve been treated with chemicals that will leach into your soil; though pine will degrade, by the time it does, you’ll probably want to change your design anyway
- Don’t fill with potting mix; it’s mostly composed of peat moss which will compost quickly and sink down, getting rid of precious air pockets; instead, use a mix of 1/3 top soil (can be found at local composting facilities), 1/3 Leafgro or compost, 1/3 existing soil
- Fill with a potting mix and replace at least 50% of it every year because it will compost and lose airspace porosity over time
- Mix about 10% by volume fine pine mulch or arborist chips (can be found at local composting facilities) into potting mix to help retain airspace porosity
- Don’t add gravel to the bottom of the pot; contrary to the popular belief that it helps with drainage, it actually does the opposite
- Raise your containers up on pot feet (or even bricks or 2x2s) to allow water to drain out
- Trash cans make great containers for deep-rooted veggies, like carrots, sweet potatoes and potatoes, and because you’re using a light potting mix, it’s easy to stick your hand in to see if they’re ready to be harvested
by Adrienne Neff, Behnke’s Graphics Department