As temperatures plummet this time of the year the lights go back on in the cold frames at West Dean Gardens. It is essential to provide a minimum of frost protection for those border line hardy plants that are lined out to over-winter. Large mature plants of frost tender perennials, that have a semi-woody framework such as salvias are lifted, potted into large pots and spent the winter in one of the light, airy, and unheated but frost free fruit houses.
Things that are cut to the ground, like dahlias, are stored in trays of old compost in a dark, frost free place such as the Mushroom Shed. These young plants will form the basis for next year's display and need to be nurtured through the difficult winter months if they are to survive and thrive. This is tough love and not killing them with kindness!
Keep them cool as too much heat will produce sappy, leggy growth which is susceptible to pest and disease attack and cause them to flop in the display house.
Give them as much air as possible consistent with maintaining
the desired minimum temperature.
Keep them on the dry side, including the atmosphere. Remember they only lose water through evaporation and transpiration and there ain't too much of that going on through the winter! We have also found that raising the pots off the cold, damp bench surface has improved our success rate significantly. We do this by making mesh frames that fit the bench top and create a 25mm gap for air circulation.
Finally keep an eagle eye out for pest and disease. Yellow stick traps are an excellent way of monitoring the presence of pests and also have a useful control effect.
Housework and Hibernation
Every winter the Victorian Glasshouses are cleaned from top to bottom. In early November we work through all of the houses throwing out the plants that we propagate annually. Next comes the cleaning and tidying the permanent stock before moving it to winter quarters. The collections here are brought together to free up the other glasshouses for cleaning, and to reduce the heating bill. To that end the overnight temperature is now also reduced slightly to hold plants under an almost cryogenic regime. Water, feed and heat are reduced to the bare minimum possible for keeping them ticking over. Attention to pest and disease control, however, becomes even more of a priority in these crowded and slightly stressed conditions. Once the glasshouses are clear the grand scrub down can commence.
Feed the Compost Heap
Of all the punctuation marks in the northern temperate zones seasonal cycle, leaf fall is undoubtedly the most dramatic. The annual foliar striptease executed by the deciduous tree population at West Dean Gardens marks the transition from growth to dormancy and, in a good year, a most lavish swansong to autumn. Once those flaming colours have faded, and are just a damp, brown mush blanketing the lawn, the serious business of leaf clearing must commence if turf and plants are not to suffer under their smothering embrace. We try and time it so that they are blown by the wind into natural collection points around the Gardens and College, without leaving it so long that they are an immovable saturated mass.
Then we go in with blowers' knapsack for smaller spaces and wheeled versions for larger areas and blow them into windrows. Then if weather and space allow we run our large tractor-mounted flail mower over them. This picks 'em up and chops 'em up at the same time, both reducing their bulk and giving the composting process a kick start. This can be duplicated on a domestic scale with a powerful rotary mower. In smaller areas they are hand collected but their ultimate destination remains the same, the compost heap. Leaf fall is part of nature's nutrient recycling scheme, so don't burn them!
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