How to Prep Your Greenhouse for The Spring?

The darkest days of winter are slowly winding down, and spring is just around the corner. This is the perfect time to get your DIY backyard greenhouse set up for the exciting growing months ahead.

When preparing your greenhouse for another season, it can be tough to know where to begin. So take the stress out of springtime prep and follow this detailed guide outlining the steps you should take to:

1. Declutter Your Greenhouse

Things can quickly accumulate in your greenhouse over the winter months. So this is the perfect time for some spring cleaning to declutter and start fresh.

What sort of things should you be getting rid of?

  • Old Plant Material: Dead plants and old leaves are hotspots for diseases and mold growth. If they look fine, you can compost them; however, if they show any signs of disease – make sure to burn them to prevent the spread of bacteria to your new plants.

  • Garden Pests: Over the winter months, many bugs and slugs may have decided to call your backyard greenhouse home and escape the icy chill outside. Take time to examine the floors, walls, any furniture and tools, and send those pests on their way.

  • Broken Items: Carefully inspect every item in your greenhouse to check if anything needs fixing or replacing. This includes pots, benches, shelves, seed trays, garden beds, and more.

2. Deep Clean Your Gardening Space

Dust off any winter cobwebs and get your greenhouse looking shiny and new again. For best deep-cleaning practices, we recommend that you:

  • Sweep the floor to get rid of any dirt and dust that has collected.
  • Wash the interior and exterior of the polycarbonate panels with a sponge and warm, soapy water.
  • Use a sponge with water and mild liquid soap to wipe down the frame, workbenches, shelves, and other surfaces.
  • Disinfect your pots, seed trays, and tools, thoroughly rinsing them. Allow them to air dry.

3. Add Ventilation Windows

Proper greenhouse air circulation is essential to avoid springtime plant diseases and ensure your garden will thrive.

For maximum airflow, we recommend placing at least two ventilation windows on either side of the roof. However, depending on the size of your DIY greenhouse kit, more may be required.

If you already have installed windows, try opening and closing all of them to confirm that they’re working correctly.

Automatic vent openers are the perfect solution for those searching for an efficient, low-effort option. They’ll gradually open as temperatures rise and close as they drop in the evenings. This guarantees that your plants still get the fresh breeze they need – without the added stress of remembering to open the windows yourself.


4. Check Your Water Source

Before you start planting, it’s always a good idea to check your water source. Pipes can freeze over during the frosty winter months, or other unexpected issues can arise.

Once you’ve confirmed that your water source is working correctly, it’s important to ensure that it’s easily accessible from your greenhouse. For some gardeners, this may be as simple as connecting a hose to an outdoor tap and extending it to your greenhouse. Others may want to set up a sophisticated automatic watering system.

Regardless of which option you choose, just make sure that the water isn’t too cold. Icy water can be a shock to young plants, causing root damage, leaf loss and a variety of other issues.

5. Get Your Soil Plant-Ready

Healthy soil is absolutely essential for a successful growing season. If you plan on reusing the soil from your last crops, there are a few steps you can take to guarantee it’s filled with nutrients and completely plant-ready.

  • Loosen the Soil: Break up compacted dirt by running a garden fork through your plant beds. This helps to aerate and fluff up the earth, making it easier for new life to grow and water to drain quickly.
  • Conduct a Soil Health Test: Over the winter months, the nutrients in your soil can become depleted. This quick test will tell you all about your soil's pH balance and nutrient levels, so you can add exactly what your plants need to thrive.
  • Add Compost and Amendments: Once you have an understanding of your soil’s health, it’s time to mix in any necessary amendments, such as natural fertilizer, elemental sulphur, compost, peat moss, or ground limestone rock.


6. Warm Up Your Greenhouse

If you’re eager to get back to gardening and want to use your greenhouse to start growing earlier – then now’s the time to warm up your space. A good heater can lengthen your gardening season and diversify the kind of plants you can grow.

During the chillier months, you should aim to keep the temperature at 4°C (39°F) or above. This will ensure your DIY greenhouse kit stays frost-free. However, if you want to use your space for germinating seeds, we suggest keeping your greenhouse between 21-27°C (70-80°F), making sure nighttime temperatures don’t drop any lower than 10-13°C (50-55°F).

Just make sure that all your windows are completely closed, so you don’t experience any unnecessary heat loss.


7. Start Your Seedlings

DIY greenhouse gardening hobbyists have countless options at their fingertips when it comes to early-season seed starting.

As long as the inside temperature of your greenhouse is roughly around 21-27°C (70-80°F), you should have no issue germinating your seeds and getting a head start on your planting season.

Some of the vegetables known to flourish in the early months of spring include:

  • Broccoli
  • Brussels Sprouts
  • Cabbage
  • Cauliflower
  • Lettuce
  • Onion
  • Peas
  • Radish
  • Spinach
  • Turnip
  • Kohlrabi
  • Beets
  • Carrots
  • Parsnips
  • Swiss Chard
  • Garlic


Explore Greenhouses   Learn More


Why Planta Greenhouses?

Back to Learn