Onions - Keeping the Stems Straight
12th Jan 2005
The greenhouse at home is alredy getting quite full with most of the onions now transplanted into cells of 60. I have used these cells for a couple of years now and have found them to be more conducive towards producing stronger and much more upright plants than even the 40 cells I was using before. The onions will stay in the 60 cells until they will be quite strong upright plants with three leaves on them and standing bolt upright. At that time they will be ready to be move on into 3 inch pots and from there into their final 5 inch pot.
The compost for the next potting stage will obviously be a stronger mix than the F2S I used within the cells. This mix will be 3 parts Levington M2 and 1 part Westlands sieved and sterilised loam from a bag plus 1 part medium grade Vermiculite. The introduction of soil into the mix will act as a buffer as well as slowly introducing the plants to the sort of growing mixture that will await them in their beds. Added to mixture will be Nutrimate at a ratio of 4 ounces to every bag of M2 used, the whole lot will be mixed up in my electric concrete mixer.
Shape and Form
There's nothing worse after potting up your onion plants to see them all flopping about in their pots, very often leaning across each other. This is really as bad as it can get, because if the onions are going to be left to their own devices, they will soon be bent. This will inevitably happen low down on the stem of the plant, the very area which needs to be as upright as possible in order to ensure that later on, your onions will have good shape or, more importantly, good form. You have to bear this in mind right through the growing season, and even more importantly when they have just been planted in their beds and starting to grow away.
I have tried numerous different ways to keep the plants supported using thin bits of wire and even going as far as to encage them between two canes using string. These days it"s a lot simpler by using the green plastic plant support clips that are available in two sizes, small and large. These are moulded in a half circle with both ends formed back in a hook shape so that they clip on to split canes. Generally the small size will be sufficient to hold up the onions right through to planting time. Initially one clip and a single cane will do the job by clipping onto the cane and bringing the other around the plant and back onto the cane forming a circle. The position of the clip will have to be decided initially at just above the young growing central shoot as you don't want this growth to start getting outside the clip. Keeping your eyes open for such eventualities is all part of the growing techniques and when you have a hundred or more plants to be supported, it can be labour intensive, It is however a job that is well worth doing.
Later on, as the plants progress, I will have two canes both taller than the first at 24 inches long. Four clips will probably be used as the plants grow giving you two full circles with the leaves totally encased inside. Again it's up to you to determine the height of these clips as they have to be positioned in relation to the growth rate of the plant. Always bear in mind that the whole point of the exercise is to maintain an upright, straight stem from the base of the compost to where the leaves part.
I might be in danger of repeating myself here and some of you will say, 'oh, I know that already' well lucky you then, because I know from the letters and phone calls that I receive, that there's many of you out there who don't realise the importance of keeping the stems straight. I know this because I judge some of the onions and their lack of ‘Form' becomes very self evident when you are handling each onion.
As the seed of Parsley apparently goes to the devil first prior to germinating, I always like to get mine in fairly early on in the year, because if it doesn't come back pretty handy from him, I still have enough time left for another sowing! Parsley is from the Umbeliferae family and therefore just as notoriously slow in germinating as its sister the parsnip. Broadcast sow the seed evenly on top of some F2S compost in a shallow tray, and gently press them into the compost with a flat board. Don't cover the seed too much, I like to cover mine with a very thin layer of fine Vermiculite, enough to keep the seed in a semi darken environment. Keep the tray evenly moist and kept on a heated bench or inside a propagator, anything from a fortnight to a month will see them germinated. When both the seedling leaves are fully extended and the true mature leaf is just showing itself, I transplant them into multicells of either 60s or 84s using Levington M2 that I pass through a sieve to get rid of some of the harder and larger lumps.