Pre-Rooted Onion 'Stuttgarter Riesen'

How to grow: Prepare the soil: Onions  and garlic prefer an open, sunny site and light, free-draining soil. If you have heavy soil, dig a generous amount of grit and organic matter into the planting area to ensure better drainage. Avoid planting in very heavy or freshly manured soil. Onions are sensitive to acidity, so if you have acid soil add some Garden Lime to the area well before planting, or a Pre-planting Onion, Shallot and Garlic Fertiliser. 

Planting: Both autumn and spring varieties can be planted straight outside into prepared soil. Loosen the soil and dig in some Pre-planting Fertiliser for added nutrients. 

Plant onion with the tips of the sets showing at the soil surface, same level at cell they have been grown in. Onions should be spaced 5-10cm (2-4in) apart with 25-30cm (10in to 1ft) between rows, and shallots 15-20cm (6-8in) with 30-45cm (1ft to 18in) between rows. 

Garlic cloves should be planted so the tip of each clove is 2cm (1/2in) below the soil surface. We suggest leaving 15cm (6in) between individual cloves and 30cm (12in) between rows. 

Aftercare: During the growing season, water if the weather is dry and give an occasional feed with a general liquid fertiliser, and keep the area weed free. Stop watering and feeding once the bulbs have swollen and remove any flower spikes when they appear. 

You might not know, but hardneck garlic varieties may produce a curly flower stem (commonly known as a scape), and cutting this offer can increase the bulb size. The scape has a fresh, garlicky flavour that is absolutely perfect for stir fries! 

Weeds can also wreak havoc on garlic crops, robbing of its essential nutrients and moisture, so keep on top of weeding, ideally by hand to avoid damaging the bulbs. 

Harvesting: Onions can be lifted fresh in summer as soon as they reach a useable size, however if you’re harvesting for storage we recommend waiting until the foliage bends over and dies down naturally before lifting. 

To lift, you should ease your bulbs out of the ground and allow them to dry outside (if the weather is fine) or in a well-ventilated greenhouse or shed.  

When harvesting garlic, we’ve found that a good indication is when their foliage starts to turn yellow and wither. Use a fork to gently remove the bulbs from the ground. 

We also recommend covering garlic bulbs in Horticultural Fleece to protect emerging shoots from hungry bird beaks! 

Storing: Onions and garlic are ready for storage when the skins are completely dry and papery. They should be kept in a light, cool and well-ventilated place either plaited in bunches or stored in nets. 

We recommend using Onion Storage Nets to keep your crops in top condition for as long as possible. Discover our range of storage accessories online for more inspiration ahead of your harvest time! 

After lifting garlic, dry off the bulbs in a light and airy space. They should ‘rustle’ when their outer skins are fully dry. We recommend storing in a cool place until needed

Guide to plant sizes: 

We have hand planted these sets/cloves into the cells to start the growing process off. These are now all rooting nicely and many will have the green shoots emerging from the top of the set/cloves. Don’t worry if some aren’t showing yet, they will.  

As soon as you can, take them out of the packaging and give them a good water. If you cant plant them straight away, put them in the garden somewhere out of direct sunlight and strong winds, keep them moist until they are ready to be planted. 

Most have 2 sets/cloves per cell, once you remove the plug from the tray, just ease these apart, be careful not to break too many roots. But they will re-produce a lot more roots once planted. 

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