In this section, we will discuss all the things you need to consider once you have your raised beds built. We talk about what to fill your raised beds with, jobs to be done before each growing season, sowing and watering tips.
Are you keen to take on a small DIY project? Why not build raised beds yourself – it’s not hard to do, it is cheaper and you can use recycled natural materials that will last you decades. Here’s an article on how Seb built our raised beds from scratch: Raised Bed Gardening – Part 1: How to Build Raised Beds from Scratch?
We ourselves only started raised bed gardening three years ago, so we can hardly call ourselves experts. But we’re keen to learn and share what we do to grow as many vegetables as possible for our table.
Whilst we touched on the compost in Part 1, I would like to elaborate on the subject slightly. Once you have your raised beds built and set in a good place in your garden that gets a decent amount of sun daily, you need to fill your beds with good quality soil or compost. Fundamentally, you have two options: to fill your raised beds with good quality soil, or you can use soilless options: compost, bags of potting mixes or even your own mixes.
If you have good quality soil (in the right clay/sand proportions) in your garden already, you can simply use that. Make sure there’s no rocks or stones in it though. If you don’t have enough, you can top it up with some Top Soil from any gardening shop. The advantages of using soil are quite obvious: it can be a lot cheaper (especially if you already have your own good quality soil). What is more, it will not compost and sink down, so you won’t need to add much each year to top up the raised beds. Another huge advantage of using soil is that the clay in it will retain water much better than soilless mixes, meaning less watering.
However, soil can be too dense and heavy, so the vegetables may grow slower and you may not be able to get multiple harvests that raised beds are well known and cherished for. You may want to add 10-12% compost to aerate your soil and add some nutrients.
Since the soil we had in our garden was awful, we opted for the soilless option, and we had huge success. The first year we filled the beds with all-purpose compost. It did settle quite a bit next year. Compost is an organic material that decomposes over time. Not surprisingly, the level of soil in the raised beds goes down every year, so you need to add more of it annually. The second year we opted to mix in some manure to add nutrients and that did wonders to the speed of the vegetable growing and the size of our harvest.
Before Each Planting Season:
- If you had some cold temperatures, it is worth warming up the soil for at least a couple of weeks before you start planting. You can find more details on warming the soil in our Raised Bed Gardening: March Guide.
- Prepare some cloches in case of the temperature dropping unexpectedly.
- Turn over the compost in your raised beds.
- Add manure/ feed/ fertiliser before you plant.
- If you’ve only used compost and it has decomposed quite a bit, you may want to add more compost to fill your beds.
- Order seeds/seedlings.
- Start growing plants indoors and transfer them to raised bed when seedlings are big enough.
Planting in Your Raised Beds
Planting in raised beds is easy. A couple of things to consider is the space that your plants needs, neighbouring plants and crop rotation.
Space: one of the biggest mistakes we made in our first year growing vegetables in our raised beds was not giving each plant enough space. Not only we sowed the seeds too close together, but we also failed to thin the seedlings as they were getting bigger. This is especially important for root vegetables, like carrots and beetroot, but lack of space affects all plants. Make sure to follow the instructions on the packet and space the plants accordingly.
Love Thy Neighbour: For the best results, it is worth investing some time in researching companion planting advice. Some plants make great neighbour, whilst others may impede the growth of each other. A full article on the best companion plants is coming soon.
Crop Rotation: Although not as essential as in growing vegetables in soil beds and allotments, crop rotation is still important. Whilst the compost in raised beds is regularly topped up, crop rotation can give extra insurance for keeping the soil-borne deceased and keeping the overall health of your beds in great shape. Here’s a great article on how to rotate crops in your raised beds.
Watering & Maintenance of Raised Beds:
There are many ways to water your raised beds. Whether you’re using a hosepipe, a good old fashioned watering can, or have drip lines and sprinklers installed, there are a few things you need to know about watering your raised beds.
There is some debate on the specific time of the day that’s best to water your raised beds, one thing is for certain. Watering in full sun isn’t a great idea. The water will simply evaporate before it has a chance to sink into the soil. What is more, your plants will get a shock from the difference in temperature between cold water and the air/soil temperature.
The advice is to either water early in the morning, or in the evening. We have a water butt collect rainwater that we use for watering raised beds. I tend to water my plants early in the morning (around 7 am) when the sun is low and the temperature of the water and air is somewhat similar.
Advocates of evening watering suggest that it is vital to replenish your raised beds with water after a day in the sun. Plants use water from the soil and transpire through leaves during the day. Providing plants with water in the evening help them collect more nutrients through osmosis when the temperature is cooler. However, it is not advisable to water the plants after sunset as the dampness may cause fungal infections of the plants.
Depending on the temperatures, weather conditions and how well your raised beds drain, you may need to water them more than once a day. The rule of thumb is to never let the ground fully dry out, day or night. If you notice the soil drying out very quickly, plants wilting or leaves turning yellow, increase the frequency and amount of watering. I was always told to stick my thumb in about an inch deep and if it’s dry, get the watering can out.
In summary, ensuring proper watering method, timing and frequency require knowing not only your plants but also considering the time of day, season and the climate in the region you live in.
Weeding: We hardly ever get weeds in our raised beds, due to the weed matting underneath, but sometimes seeds blow over from elsewhere. Weeding is extremely easy, aerated compost makes it easy to pull the weeds out!
Settling: Whatever soil mixture or compost you fill your raised beds with, you can expect a certain amount of settling. You should be prepared to supplement the raised beds almost every year with more soil/compost.
Preparing Raised Beds for Winter: if you are not planting winter crops or growing overwintering vegetables, at the end of the growing season, clean up all dead plants and get rid of all the weeds. You may choose to add some compost to ensure that a nutrient-rich environment gives you a head start next spring. You may also choose to cover the soil over winter to ensure all the nutrients don’t wash away and protect the beds from weathering. This helps with the soil warming so you can start planting earlier in the season. We personally don’t cover our beds over winter but warm the soil a few weeks prior to planting in early spring.
If you want to build your own raised beds, check out Seb’s guide on how he built ours, here. If you are ready to plant, we are putting together month-by-month raised bed gardening guides: