Mibuna is a traditional Japanese green crop, ideal for greenhouses in winter. Like mizuna, it is a member of the cabbage family and produces green leaves for salads and cooking over a long period.  It is grown in much the same way.  It is less hardy and productive than mizuna, but its narrow strap-like leaves (often with a white midrib) have a more spicy flavour that gardeners enjoy and some slugs don’t (though some like it hot).  It can be harvested as whole plants, but excels as a cut-and-come-again crop.

Seed sown now in containers or borders can produce leaves from October to April or May next. Add in plenty of compost, and sow seed thinly in drills 1cm deep.  Border rows should be about 30cm apart.  Keep the soil moist: dryness encourages bolting, especially in spring-sown crops.  Watch out for flea beetles and slugs.  Cut off and compost overgrown leaves and any flowering stems that appear; it diverts the plant’s energy into growing more fresh leaves.  Use leaves while they are still young.  Eat them raw in salads or lightly steamed or pickled.

Late Vegetables

This summer’s drought may make vegetables scarce and expensive until next year. Plan now to maximise the cropping potential of your tunnel or glasshouse and to leave no square metre unproductive over the winter.  It is too late to sow spring cabbage seed outdoors for planting out in the autumn, but raising plants in your greenhouse now may bring on seedlings faster and have them big enough to plant out on time.  If you do, harden them off before planting out and protect them from hungry pigeons.  Alternatively, plant them in the greenhouse for an earlier crop.  Plant single seed potatoes in large pots now, and they should still have time to mature before midwinter.  Beetroot, white turnips and kohl rabi will produce small but tasty roots, and you can eat their young leaves too.  Rocket, oriental greens such as Pak Choi, kale, winter lettuce, corn salad, Texel greens and winter purslane can be sown in succession for salads.  Calabrese, French beans and Florence fennel can all yield well in greenhouses from August sowings if the early winter is not too cold.

If your greenhouse is full already, bring on seedlings in cell-trays and then small pots until planting room becomes available. You can sow radishes, baby leaf greens and other short-term crops between rows of slower growing crops, as they will be harvested before the space is needed.  You can still have your five a day!

The Master Victorian Greenhouse from Janssens

This lovely Master Victorian Greenhouse has just been constructed by us in Cong, County Mayo and our customer is delighted with it and has kindly sent in this photograph.  The Master Victorian Greenhouse from Janssens is available in four sizes, the one pictured is the largest of these at 3.1m wide and 6.06m long.  With a generous height at the sides of 2m, lots of ventilation and with a very strong ‘box section’ aluminium frame it is no surprise that this is a very popular model.

A stunning Master Victorian Glasshouse


A sweet idea for Greenhouse growing (Sweet Potato that is)

Sweet potatoes are related to morning glory and not ordinary potatoes. It’s possible and fun to grow your own. Plants are usually raised from ‘slips’ taken from sprouting tubers. You can sometimes buy them online or in a garden centre; ‘Beauregarde’ and ‘Georgia Jet’ (with orange flesh) and ‘T65’ (white flesh) are suitable varieties. ‘O’Henry’ produces tubers close to its base and is good for container growing.
Bought tubers can be from varieties less suitable for Irish conditions, but you can still get a small crop from their shoots. Organic tubers unsprayed with sprout inhibitor are best. Stand the tubers half-submerged in lukewarm water with their narrow ends down. Place them in a warm sunny spot to sprout, changing the water daily. Cut off the sprouts when they are about 15cm long. If still rootless, root them in warm water or cutting compost and plant when rooted. Soak bought-in slips overnight in lukewarm water before planting.
Plant them deeply (to encourage tubers to form at the nodes) in light, well-drained, fertile, neutral or acid soil in full sun. Always keep plants and tubers above 10°C/50°F. Give warmed water when needed, and feed weekly with tomato feed. Tie up the sprawling stems or they will root into the ground at the nodes. Green leaves can be eaten in salads or lightly cooked like spinach, but don’t take too many or you will reduce the tuber crop. Dig up the tubers after 3-4 months when the foliage turns yellow and dies back. Avoid damaging them as they bruise easily. Dry the roots in the sun for a few hours and then cure them for five days at 30-32°C / 85-90°F and 85-90% humidity. Store them above 10°C/50°F in good ventilation and either eat them soon or blanch and freeze them.

Sweet Potato

Preventing damage from snow

As the whole country is bracing itself for the ‘Beast from the East’ we would like to advise customers with Glasshouses that once it is safe to venture outside you should remove snow as it is surprisingly heavy and can collapse structures if allowed to build up excessively.

If you have an electric heater for use in Greenhouses (specially sealed for a wet environment) you could leave it running as the warmth may help to melt snow before it has a chance to build up. If you have a direct fired heater – e.g. a gas heater that works like a gas hob inside a metal cover, only leave it running if you can be positive that there is a fresh air supply to it that will not get blocked (otherwise it will burn up all the oxygen and produce carbon monoxide with potential disastrous consequences).

Any number of ways (such as soft bristled brushes, sheets, mop handles etc.) can be used to dislodge snow but whatever you choose try not to damage your powder coated frames or scratch the glass in the process.

It is also possible to prop the roof inside your Greenhouse as an extra precaution if you can lay your hands on suitable equipment and have the know how but of course this should be done before snow builds on your structure in case it could collapse while you are in there.

We hope that everyone will be safe and well which is the most important thing, your Greenhouse can always be replaced – and you may even have insurance to cover it, but of course it is not worth taking any risks to protect it.

Carrots for May

You can buy carrots in the shops almost any time, but nothing beats your own early carrots for flavour and juicy crunchiness, harvested just before eating in spring. Carrots sown in a tunnel or glasshouse in February are ready to eat about late May, well before any crop sown outdoors would be ready. In milder areas, seed can be sown in January for even earlier crops.
The traditional varieties such as ‘Amsterdam Forcing’ or ‘Early Nantes’ are as good as any for early sowing. Border soil for sowing carrots should be light, stone-free, without recently added manure or compost and above 5°C. Sow the seed thinly in drills about a centimetre deep and 20 cm apart. If the soil is very poor you could sow them in large pots of prepared compost or compost/soil mixture. Cover the drills or pots with fleece on cold nights to keep the soil as warm as possible: the warmer the soil the faster they germinate and grow. Protect the emerging seedlings from slugs, and as soon as they are big enough to handle thin them out to about five centimetres apart. Do not let the soil dry out, as it stalls growth and the carrots can split when watered again. If not eating harvested carrots right away, cut off the leaves to prevent them drying out and shrivelling the roots.

Delicious carrots

Newest addition to our display

Arcadia Plus Lean-to GlasshouseThe latest addition to our Greenhouse display area is this lovely Janssens Arcadia Plus Lean-to.  We configured this one to include Twin Wall Polycarbonate Glazing on the roof – which diffuses direct sunlight and helps retain heat, and we have clear toughened glass on the walls.  While perfect for growing plants this Greenhouse would also suit the increasing number of customers who want a room with a view in the Garden to relax and read a book and drink a glass of wine.  I’ll have to take another photo when we have the table and chairs and bottle of wine in it, but all in good time.

Merry Christmas

We wish all our customers and colleagues a lovely Christmas and all best wishes for the coming New Year.

May the road rise up to meet you, may the wind be ever at your back, may the sun shine warm upon your face and the rain fall softly on your fields.  And until we meet again may God hold you in the hollow of His hand.

Radishes – our blogging horticulturalist Peter Whyte extols its virtues

If radishes were harder to grow, we might plant them more! Maybe because their fast and reliable growth makes them an ideal crop for children to plant, adults tend not to bother with them so much.  But if you are sowing green salad crops in autumn and early winter, why not enjoy some crunchy fresh radishes with them?

Sow the seed very thinly in drills about one centimetre deep and fifteen centimetres apart. The soil should be tilled finely with no clods.  Keep the soil moist and as warm as you can in winter, watering them when needed with water that has been stored a few days in the greenhouse to avoid chilling the plants.  Cover them with bubble-wrap on frosty nights, but remember to take it off again in the mornings.

Warm moist conditions and radishes are attractive to slugs, so take precautions against them: one slug can wipe out a whole row of seedlings in one night.

Some radish varieties are better than others for winter sowing under cover. Check the seed packet before you sow, but try some anyway – radishes are very accommodating and the seed is not expensive.

Pesto and radish bruschettas

Soil Warming Cables – a Christmas Gift Idea

Christmas is coming and people are getting stressed by questions such as ‘what present can we get for (fill in the name yourself)?’ If they have a tunnel or glasshouse, how about something to increase their enjoyment of it?  They could use a soil warming cable in so many different ways that it is almost certain to expand the range of plants they can grow and/or extend their growing season.

The theory is simple. The cable is buried below the surface of sharp sand.  When warmed by electricity it warms the surrounding sand and any seedtrays or pots sitting on it.  Soil temperature affects plant growth more than air temperature.  Seeds germinate faster, cuttings root sooner and growth continues when the air temperature drops a bit too low for normal growth.

Insulating fleece or bubble-wrap over the plants will protect them from a few more degrees of frost due to the rising heat.  Adding a thermostat will save electricity when the sun warms the soil naturally; see https://greenhouseireland.ie/accessories/ .

You can heat a whole bed or just a small propagation area, but if the latter it’s more convenient to have it on a raised bench or staging in which case you should place insulation underneath it.

Electricity and water are an unsafe mixture. Make sure you use a qualified electrician to lay on power to a glasshouse or tunnel, and follow the installation instructions carefully.