Potting Sheds – Fertilisers and Additives

There is nothing worse than going to your shed next spring to get some fertiliser, only to find that you haven’t enough for the task at hand. Personally I use quite a lot of some types and less of others so I buy them all in fairly large quantities and I find some will last me for a few years provided they are stored in a dry environment.

At this time of year, it pays to have a good look through your potting shed, or wherever you keep your gardening sundries such as fertilisers etc. There is nothing worse than going to your shed next spring to get some fertiliser, only to find that you haven’t enough for the task at hand. Personally I use quite a lot of some types and less of others so I buy them all in fairly large quantities and I find some will last me for a few years provided they are stored in a dry environment.

Additives

The main fertilising soil additives that I use are hoof and horn, superphosphate of lime, sulphate of potash, calcified seaweed and carbonate of lime. I use these in my various mixtures, particularly for root crops such as parsnips and carrots. Another product, of which I like to have plenty, is fine grade vermiculite which I use quite a lot in most of my various potting mixtures. There’s no doubt that buying any of the above products in large quantities gives you considerable savings over the small retail packs and Garden Direct offer a marvellous mail order service where they stock most products under the sun. Just telephone your order on 01992 441 888 and if it is over £40, there are no extra delivery charges and the material will be sent straight to your door.

Leeks

Next week I shall start to take some bulbils off the leek heads and root them in a mixture of 3 parts Levington F2 to 1 part vermiculite. Prior to that though I shall give all the heads a spray of Tumblebug to make sure that there are no bugs lurking around in the head. The heads should now be undercover as they are very prone to root on the head if they are subjected to any moisture. Premature rooting on the head can be a problem as it’s often difficult to untangle them and, more importantly, they will have started to root much too early, resulting in the leeks going to seed during the growing season, long before they achieve their full potential.

Having Everything Ready

How I start them off will be explained next week but do make sure that you have everything to hand by way of compost, vermiculite or perlite, depending on which one you prefer. The next step is to switch on the propagating bench or propagator; in my case I shall be rooting a few hundred so the propagating bench will be heated up. The first thing is to loosen the sand that covers the cable so that the crust (which forms when the bench has been kept dry for weeks over the summer months) is taken off. If you followed my greenhouse cleaning rota last week, the greenhouse should be perfectly clean but do make sure that the sand on the propagating bench is well and truly moist. Some novice growers don”t appreciate that the heat from the warming cable that’s buried in the sand is transferred from the cable via the moisture in between the sand particles. It’s important that the sand is always kept moist throughout the period that the bench heating is on. Failure to maintain an adequate moisture level can lead to disasters, particularly when the root systems of leeks and onions in pots are well advanced and sitting on the sand. If the sand is dry, then the compost in the lower regions of the pots will become dry and if not spotted early enough, the roots can die off with the leeks and onions struggling to achieve their optimum potential from that point on.

Cleaning

If you intend to root your leeks in trays or pots, do make sure that they are all clean and I don’t mean just giving them a tap on the bench to get rid of any old loose compost. The pots must be washed in water with some added Armillatox at the strongest dilution rate. I try and pick a nice dry day and the long galvanised bath that I use for washing my long carrots and parsnips is filled with the above solution and they are all given a good clean with a scrubbing brush. I don’t bother drying them with towels and they are left to air-dry on a temporary staging and then taken back to the greenhouse when bone dry. This might appear to be a lot of trouble, but the fact is that disease spores can hide in all sorts of crevices and particularly in old compost so it’s best to start off with everything as clean as possible. If you are using multicell units in seed trays then it’s far better to buy new cells every year and the ones I use a lot of are Plantpak 40s, (40 cells in a full size seed tray) Plantpak 24s and 15s.