Creative with Cucumbers!

Crispy, crunchy, and thirst quenching – cucumbers are a summer supermarket staple. So much so, that some Kiwi kids are said to believe these curcubits grow inside a plastic skin! If you’re not into the shrink-wrap, shopping trolley version of cucumbers (and their gherkin cousin), now is the time to start growing these delicious vegetables in your own tunnelhouse. 

Cucumbers require reasonably high temperatures (between 23and 29 degrees Celcius) to thrive. If you live in a warmer part of the country, October is the month to pop the seeds into the tunnelhouse itself. If you’re in a cooler spot, wait until later in the month for this, or delay until November, or even (in the case of mountainous regions) December. Regardless of where you live, if you are still enjoying your autumn and winter planted veges from the tunnelhouse, and plan to do so right through spring, there’s no need to oust them prematurely to make way for cucumber plants. This obliging vegetable will happily wait to be planted until you have space ready for it.

Source

We live in an age where every gardener wants to be a seed saver. That’s a good thing, but sometimes, saving your own cucumber seed doesn’t work out quite as you expect. That’s because many of our favourite varieties are ‘hybrid’ cucs. A hybrid vegetable is the result of two different varieties of plant being deliberately cross-pollinated to create a desired result. Unfortunately, when the seed of the progeny is sown the following year, it is unlikely to produce a vegetable which is identical to its parent. It will have reverted to an earlier variety, and in the case of your cucumber, it will not be the one you were hoping for. If your favourite cucumber variety is labelled ‘F1,’ that’s your clue that it won’t deliver the goods second time round, and that you need to start from scratch with store-bought seeed.

Cucumbers come in a wide range of varieties, so there are plenty of choices. If you are growing in a limited space, choose a compact, bushy variety or one such as the Lebanese cucumber, which produces smaller fruit. If you’re a small household, and want to avoid waste, choose a mini variety such as Cucumber Crunchy F1. And if you’re a pickle-lover, be sure to head to the mini-cuc cousin, the gherkin.

While cucs and gherkins grow readily from seed, they are also widely available in garden centres. If buying potted seedlings, take a magnifying glass with you, and check carefully, on both sides of leaves, for pest insects and their eggs. If there are any signs of invasion, leave the plants on the shelf!

Ground work

Cucumbers (and gherkins) enjoy growing in ground which is fertile, textured, and humus-rich. When preparing a growing spot for them in the tunnelhouse, dig in plenty of safely made, mature, nitrogen-rich compost. Although cucumbers like a little lime, your tomatoes don’t, so if you plan to use the same ground next year for tomatoes, skip the addition of lime (something the cucumber plants will tolerate). Water the ground well, 24 hours prior to sowing seed or planting seedlings.

Cucumbers resent having their roots disturbed, so if you plan to train these climbing plants up stakes or trellis, anchor your supports firmly into the ground before you place the seeds or plants in the soil. If you don’t, you will cut through delicate roots, and your plants my sulk as a result. If you will be using twine to support your growing vines, put these in place before you plant so that you avoid  standing on the ground and compressing the soil.

Sowing

Sowing into pots

If you are raising your seeds in containers prior to planting out the resulting seedlings, sow into peat pots (or pots which you make yourself from toxin-free paper). This means that you will be able to plant the seedlings, pots and all, into the tunnel house when the time is right, without disturbing roots. Note: some gardeners have tried using cardboard tubes (such as the sort which come inside kitchen wrap) as planter pots. However, these can be sturdier than they look, and can inhibit root growth before they are ready to decay in the soil.

Fill your seedling pots with quality seed raising or vege mix, water it well, and sow the seed, about 1cm deep, into the growing medium. Cover the seed with loose soil (don’t compress it). If you have a seed raising mat, pop the pots onto it. Covering the pots with a sheet of plastic (at night, only) can speed up germination. If the weather is slow to warm up, water liquid feed onto your seedlings to provide nutrient until they can be transplanted into the tunnelhouse.

Sowing directly into the tunnelhouse

Sow your seeds into prepared ground (see above) in groups of 3. Each group of seed should be sown 60 to 70cm apart. Once the seed germinates and grows on for a week, pluck out the two weakest seedlings from each group, and let the third grow on.

Maintenance

Once the seedlings are established in the tunnelhouse, liquid feed them with nitrogen-rich fertilizer every 3 weeks after flowers appear on the vines. This feed can be brewed by soaking safely made compost with blood and bone, seaweed, and comfrey leaves. Keep the ground beneath the cucumber plants weeded, and the tunnelhouse well-ventilated to encourage the air flow necessary to deter fungal disease. Tie the vines to their supports regularly so that the foliage does not collapse back onto itself.

If you spot signs of ‘rust’ on leaves, snip off the affected foliage and dispose of it in your waste bin (not the compost). If you see signs of aphids, gently squish the insects with your fingers, and treat the foliage (not fruit) with soapy water spray*every 3 days until the infestation reduces or disappears.

*Make your own soapy water spray by dissolving half a teaspoon of hard bathroom soap in 1 litre of very hot water, cooling the water completely before adding it to a clean spray bottle.

Tips

Most cucumbers require insect pollination to form fruit. Encourage insects into your tunnelhouse by planting insect-friendly flowers around the doors, and by moving one or two potted marigold plants into the greenhouse when they are in bloom.

Harvest your cucumbers as soon as they are mature so that the vines do not have to work unnecessarily hard to support them.

When using ties to anchor the cucumber vines to their supports, avoid soft woven, cotton twine. It tends to hold onto moisture and can cause fungal disease to develop in the stems of the plants. Choose strips of nylon pantyhose, instead

Drooping, wilting foliage may not be due to a lack of moisture in the ground. Over-watering can do even more damage as it swamps the soil and prevents oxygen reaching roots. Water only when the ground feels dry up to the second knuckle of your finger. Water deeply, to encourage roots to grow down into cooler ground.

Water your cucumber plants in the early morning so that excess moisture evaporates during the heat of the day and does not collect at night to cause a damp, humid environment.

Discourage disease by always water the plants from the base, avoiding wetting the foliage.

Grow Me Now

September

Sold on Strawberries!

Strawberries are a longed-for summer treat, but they so often disappoint. From failing to fully pollinate, lacking flavour, becoming marked by birds, slugs, and snails, rotting before they’re ripe, and simply not returning a decent number of berries, strawberry hassles mean many gardeners give up growing this delicious fruit. If this sounds like you, there is another way to get the crop you crave – and it’s by growing your strawberries in a tunnelhouse. What’s more, strawberries in the tunnelhouse ripen so much earlier than those outside, that you’ll have the ground free for tomatoes and other heat-lovers by the time you need it. As a bonus, tunnelhouse strawberry plants are likely to produce more fruit than those grown outdoors, so you don’t need the same number of plants. And your berries will be super-sweet because of ripening in the warmest of conditions.

Source

Strawberries fruit from spring through until autumn, depending on variety, with ‘Monetrey’ being one of the latest varieties. If you have space in your tunnelhouse to grow strawberries throughout the warmer months, choose a range of varieties. If you need the space for heat-lovers in late spring, choose an early maturing strawberry such as ‘Pajaro.’ If you are already growing strawberries in your outdoor garden, and the variety suits your purposes, dig up a few young plants that have formed on ‘runners’ last season, and use them in your tunnelhouse.

When purchasing plants from the garden centre, inspect them carefully (on the underside of leaves as well) for signs of aphids and other sap-suckers. Once these pests reach the warmth of your tunnelhouse, they will romp away if not checked.

Groundwork

Whether you intend growing your undercover strawberries in the tunnelhouse bed, or in containers, preparation is the same. The soil needs to be rich, loose, and free draining. Dig in lashings of compost made with ingredients that include sterile animal manure and decayed kelp, and add a sprinkling of bone dust. Strawberries are acid-loving, so skip the lime. If you are using inorganic fertilizer, choose one specifically for strawberries, or which has a balanced NPK ratio. Dig all ingredients in deeply, and water the beds or containers well. Leave planting until the next day, once the growing medium has soaked up the moisture and had time to drain.

Transplanting

Strawberry plants can be grown a little closer together in the tunnelhouse than you would outdoors because there is less leaching of nutrients, undercover. Drainage is also more controlled so there is no need to raise the plants up on mounds. Simply make shallow depressions in the bed (or your containers) about 1.5 hand widths apart. Press the plants firmly into the soil, and bring the soil around them without covering their central crown (the point in the centre of the plant from which the leaves grow). The crown should always be above soil level. Lay a light mulch of straw or untreated wood shavings around the plants.

Maintenance

Water the plants before the soil dries out completely, and give them a liquid feed every 7-10 days until fruit begins to set. Check carefully at night, with a torch, for slugs or snails, and remove any you find. Once fruit begins to ripen, keep it free of fungal disease by ventilating the tunnelhouse day and night. Cover doors and vents with netting to exclude birds, or use a specially fitted Tunnelhouse screen door. Snip off (never pull) runners as they appear (‘runners’ are new, young plants which form on a long stem which branches off from the main plant). This will help keep your plants fruiting. Harvest the berries with scissors.

At the end of the fruiting period (when the plants are no longer producing flowers), remove containers of plants outside and into a sunny position. If you have grown your strawberry plants directly into the greenhouse bed, dig them up, and replant them in a spare space in the outdoor garden.

Tip

If using pea straw mulch, take great care to get it from an organic source or to make certain it has not been tainted with Glyphosate. Even a trace of the chemical will damage or kill tomato plants.

If signs of fungal disease appear, move mulch away from the plants to allow for greater air flow. Remove any diseased fruit immediately.

Towards the end of fruiting, allow a handful of runners to develop. Press them into containers of potting mix while they are still attached to the parent plant. Once they are rooted, snip off the runner. These young plants will provide you with next year’s greenhouse crop.

Grow Me Now!

August

Tempted by Tomatoes!

They’re the summer favourite that gets gardeners talking – and the one plant, more than any other, that sees a grower invest in a tunnelhouse. Which makes it even more unbelievable that this South American native once aroused so much suspicion when first introduced to Europeans, that they had to be persuaded to eat it! Today, the popularity of the tomato continues to grow, and the trend, over the last few years, toward planting heritage tomatoes, has only increased excitement about the fruit. While Kiwis in cooler regions grow their tomatoes under cover, those in warmer climes are often turning to crop tunnels to provide a well-protected, blemish-free crop. 

Source

The depths of winter may not feel like the time of year to be germinating tomato seed, but unless you want to be buying seedlings at the garden centre (where there is limited choice of variety) August is certainly the month to start sowing. When choosing seed, there are a few decisions to be made. Tomatoes fall into two broad categories: indeterminate (vine-style) and determinate (bush-style) plants (both are suitable for a tunnelhouse or crop tunnel). Within these two categories, both commercial and heritage tomato varieties are available. The garden centre will be able to supply you with seed of regular tomatoes, and a few heritage varieties, but for more exotic choices, check out Kings Seeds, Koanga Institute, and Trade Me. Or ask around on Facebook gardening groups.

Ground work

Sow your seed into a punnet of quality seed raising mix placed on a sunny window ledge or propagation pad. Tomatoes prick out easily, so once the seeds have germinated, and have their first true leaves (rather than their ‘germination leaves’), transplant them into individual containers of tomato potting mix. Be guided in container size by your climate, and the indoor or propagation space you have available. (In cooler parts of the country, it will still be too cold to place the seedlings in the tunnelhouse in September, or even October, and they may need to grow on, indoors, for several weeks. Make sure their pots give them the root space they will require.)

Once your tomato seedlings are growing, it’s time to prepare your tunnelhouse to receive them. Tomatoes can be in the ground for 6 months or more so it’s important to pile in the nutrients from the start. Dig in plenty of quality compost (a source of nitrogen, but also of the potassium and phosphorus, on which tomatoes thrive). If your compost hasn’t included kelp, add it to the soil, now.  Tomatoes prefer a pH of 5.5-6.5, so don’t add lime to the ground unless it is particularly acidic (a soil test kit can help establish this). The roots of tomato plants are shallow, but long, and stretch out horizontally. They don’t enjoy negotiating obstructions, so mix all your ingredients into the bed of the tunnelhouse well, and crumble up any lumpy material. Water the bed deeply, at least twice before planting, and keep it weed-free.

Transplanting

Tomatoes can go into the greenhouse anytime from late August onwards, depending on where in the country you live. If your location is prone to frost then plant in the tunnelhouse late October or even November, especially if the weather is cooler. When transplanting, use a trowel to create pockets 70cm to 90cm apart. If using stakes (rather than twine) as supports, push them into the soil beside the holes before you plant, so you don’t disturb roots. Water each planting hole well, upend the seedling container to ease out the tomato plant, and place the seedling gently in the hole. Lightly firm the soil around the base of the plant (note: you are unlikely to kill a tomato seedling by planting it too deeply, so if your plant is ‘leggy,’ set it down further in the hole, for added support).

Maintenance

As your tomato plants grow, water them deeply once or twice a week. (This encourages the roots to grow down to cooler soil. More frequent, shallow watering, only encourages roots to invade the surface area, which quickly leads them to over-heat and dry out in hot weather.) Water the plants with a liquid feed of kelp and sterile animal manure every 7-10 days until flowering commences. After that, water with liquid kelp only (too much nitrogen encourages foliage at the expense of flowers).

Unless you are growing grafted tomatoes (in which case refer to the growing instructions that came with them), remove the lateral shoots from indeterminate (vine) tomatoes to encourage the plants to grow up, rather than out, and to hasten flower production. Tie the vines to stakes, or guide them around twine supports, as required. Determinate (bush) tomatoes will also require support. Provide it in the form of a framework or tomato cage.

Keep a watch for sap-sucking insects such as aphids, and squash them with your fingers in the first instance. If the pests persist, apply a spray made from 1/4 tsp hard bathroom soap dissolved in half a litre of boiling water that has been left to cool completely. Repeat every 3-4 days. Note: if you are growing organically, there is no need to completely rid the plants of pests – a healthy balance is what you are aiming for because the general strength of the plants means they can hold their own against a degree of pest attack.

Keep the tunnelhouse well ventilated day and night, promptly snip off any leaves that attract disease, this will also help with airflow and light transmission and harvest fruit as soon as it is ripe to take the pressure off the plants.

Tips

Some gardeners like to grow their tomatoes in fresh soil each season, but if disease hasn’t been a problem in the previous season, you may decide this isn’t necessary. 

Always try to grow your own tomatoes from seed. To buy at the garden centre is to risk bringing aphids, white fly and other pests into your tunnelhouse.

When sowing seed, cover the seed containers with a sheet of perspex or glass to prevent mice digging them up (in August, rodents are on the hunt for any food they can find).

If raising seed without the aid of a germination pad, try popping the seed containers inside a plastic bag as they sit on a sunny window ledge. Leave one end of the bag open to avoid over-heating and ‘cooking’ the seed. This mini greenhouse effect can hurry along germination.

 As soon as you start sowing tomato seed, begin soaking kelp and sterile animal manure in a large barrel of water. This will be the liquid feed for your plants until flowering time commences.

Tomatoes that are indeterminate love to grow in height. Use your top aluminium purlin in the Tunnelhouse as a support to tie you strings on and these can be adjusted as the plant grows. A simple tent peg or similar at the base of the plant can be used to tie the string on and wind around the stem of the plant as it grows. 

Once you discover a variety of tomato that you favour, keep the seed from it for sowing again next season. To collect seed, take pulp (containing seed) from a ripe tomato, and smear it onto a folded paper kitchen towel. Leave it to dry thoroughly over a period of days, then snip up the individual seeds (paper towel and all) and store in a sealed envelop or jar (don’t forget to label with the date and description).

Grow Me Now!

July

Coriander for the Culinary!

It must surely rank among the most pungent of herbs, and there’s no doubt that you either love it or loathe it. That’s because, genetically, coriander divides the population in two, with some experiencing it’s taste as ‘soapy’ while others find it delicious.In India, coriander is known ‘The King of Herbs,’ and is used throughout the nation. In the south, the population uses its fresh, green foliage, in a variety of dishes. In the north, it’s the dried, ground coriander seed that is sought after for use in rich, spicy sauces. Coriander is a value-for space herb in the tunnelhouse as its root can also be used in cooking. Coriander prefers to grow into cooler weather – in conditions that are too warm, it quickly runs to seed. It makes for a perfect winter crop in the greenhouse, in cooler regions, or in a crop tunnel in warmer climes.

Source

Coriander seed is not difficult to locate on the garden centre shelves, however it is best sown thickly, and there is usually only a scattering of seed in a packet. Better by far, is to purchase food-grade seed in bulk, for a fraction of the price. This can be found in the likes of Bin Inn or Asian food suppliers. Once you have coriander growing in your own garden or greenhouse, simply let a few plants bolt, and collect the seeds when they are dry. Left to its own devices, coriander readily self seeds, in which case you may never need to sow it again!

Ground work

Coriander is all leaf, which makes it a nitrogen-hungry herb. Give it what it requires in the form of plenty of sterilised manure, and lashings of compost. If you don’t have access to organic ingredients, dig in a scattering of high-nitrogen fertilizer. There is no need to add lime unless your tunnelhouse soil is significantly acid, as coriander is tolerant of a range of pH levels. The seed does not like to struggle through the ground, so make the soil as fine as you can, and keep it free draining. In winter conditions, even in the tunnelhouse, coriander appreciates sun, so don’t hide it in the shade of climbers or tall, bulky brassicas, or silverbeet.

Sowing

If you enjoy coriander, you will never have enough of it, so sow plenty, and freeze it for summer, when it is too warm for it to grow without running to seed. If you are growing it to freeze, sow the seed thickly in 10cm wide rows. If you want to pick just a few leaves daily, sow seed 2-3cm apart. However you do it, bear in mind that coriander seeds are ‘conglomerate,’ as are the seeds of beetroot and silverbeet. Conglomerate seeds produce more than one plant from a seed, so take this into account when spacing. Cover the seed with twice its depth of soil, water deeply, and place a non-treated board over the row to lock in the damp until germination occurs. After that, water frequently. Note: coriander seed has a hard outer coating which means it is slow to germinate (taking 2-3 weeks in tunnelhouse conditions). Consider soaking the seed in warm water for an hour prior to sowing to hurry along germination (it floats, so you will need to place a saucer over it to keep it submerged).

Maintenance

Coriander doesn’t enjoy competition, so keep the bed well weeded. Visit the tunnelhouse after dark, with a torch, to pick off any slugs and snails that are about. Coriander can attract fungal disease, but this can usually be managed by keeping the tunnelhouse well-ventilated. Aid air movement around the young plants by thinning as you harvest.

Tips

Although you may find coriander plants for sale in gardening centres, it is best grown from seed due to its tendency to bolt when transplanted.

Coriander is slow to germinate, taking up to 14 to 21 days, depending on conditions. It can be helpful to mark the row by sowing a few fast-germinating radish seed with your coriander.

Avoid coriander bolting by keeping the ground damp.

In dry conditions, white fly will quickly colonise the plants. Don’t let the ground dry out.

To get the best value from the plants, harvest the leaves before a central stem starts growing. Once this happens, the leaves become spindly, and the plants are all ‘stalk.’

Coriander freezes ‘like a dream.’ Chop it finely and free-flow it in snap lock bags. Use it frozen (don’t allow it to thaw before adding it to dishes).

Grow Me Now!

May

Pop in Some Peas!

Shelling-peas take up quite a lot of space in relation to the harvest they return, so deciding whether or not to grow them in the tunnelhouse in the off season can be fraught. However, sugar snap and snow peas are a different story because their entire pod is eaten, which increases their return for the valuable space they occupy. ‘Snaps’ and ‘snows’ sown in autumn will produce pods in early to mid spring in cooler parts of the country, and earlier in mild regions. When the vines are spent, they can be dug back into the ground provided they are disease-free.

Source

Outside of spring, it can be infuriatingly difficult to locate sugar snap and snow pea seed, but if your regular garden centre doesn’t have any on the shelves, head to the likes of Trade Me or Kings Seeds. Better still, if you have grown these peas in your own garden over spring and summer, check the vines for dried pods and seeds you can sow. Peas do not cross pollinate easily, so if your different pea varieties have been growing at least 3 metres away from each other, the seed is likely to be true. If you have a choice, sow dwarf varieties of snow and snap peas (some dwarf varieties grow just 60cm high) so they cut out less light from your other undercover edibles.

Ground work

Peas are shallow rooted so there is no need to dig more than half a spade deep when preparing your tunnelhouse soil for seed sowing. Peas don’t appreciate wet roots, nor will they tolerate drying out, so add plenty of well-made, humus-rich compost into the ground to act as a gentle sponge for moisture. As your summer crops will have used up all the nutrients you added in spring, add a scattering of nitrogen, and chopped kelp to the bed, and dig it in well. Soak the pea bed with water the day before sowing, and leave it to drain. Prepare a few buckets of liquid feed by soaking quality compost plus, comfrey leaves and kelp. Once the bed is ready, erect trellis (light plastic trellis is sufficient) behind the sowing area, and secure it.

Sowing

Soak your pea seed for an hour before sowing to promote swift germination (don’t leave it any longer or you risk the seed rotting in the ground before it sprouts). Use a small dibber to make 3cm deep holes, 3-4cm apart, in the pea bed (this is closer than you would sow if you were working in the garden, because you will be growing in optimal conditions, and nutrients won’t be washed out by winter rain). Drop one seed into each hole, and cover with soil. Tender shoots are a target for slugs and snails, so go hunting for these pests at night, with a torch. If using slug bait, take special precautions around children and pets, as it will not break down in the tunnelhouse as it would outdoors (greenhouses are also a magnet for cats that like to sun themselves in its winter warmth).

Maintenance

Water the pea bed only when the soil requires it. To test if water is necessary, push your finger into the soil up to your second knuckle. If it comes out clean, it’s time to water. If soil adheres to it, wait a little longer to add moisture. Make every second or third watering a liquid feed. Sugar snap and snow peas can grow to almost 2 m high, so your support will eventually need extending. This can be done by using strings to lead the vines horizontally along the inside of the greenhouse (keep them away from the roof space so they don’t block out the sun). Alternatively, nip out the growing tip once the height becomes unmanageable.

Peas are self-pollinating (they don’t require insects to do the job for them). However, by gently tapping the vines, once they are in bloom, you will encourage pollen to drop from one flower onto another, as it needs to do for the flowers to form pods.

Tips

Birds can destroy pea vines by devouring tender new leaves and growing tips. Net your tunnel house door to prevent birds entering, or use a special screen door.

Grow-lights will help your vines to grow vigorously, by adding extra light-hours to winter days (peas require 6-8 hours of sunlight per day). Always check with an electrician before installing grow-lights, and have this done professionally if required. Remember: too much extra light is not beneficial, so do your research – plants need rest, too!

Pea vines sometimes need to be ‘persuaded’ to reach for their trellis. Head them in the right direction with the help of a few twigs pushed into the ground, on a lean, toward the trellis.

Sugar snap and snow pea pods are mature when around 5cm long but can be harvested when they are half that size. Pick the first pods when they are small, to encourage others to form. Keep harvesting regularly so the vines keep producing.

Make the most of your precious out-of-season pods by lightly steaming them, and serving them cool with a dressing made of equal parts of tahini, honey and cider vinegar. Sprinkle over toasted sesame seeds. Delicious!

Grow me now in May

Love Leeks!

Source your supply

Ground work

Transplanting

Maintenance

Tips:

If you’re looking for a change with leeks in the kitchen, try sautéing them in olive oil with a little chopped garlic and plenty of finely ground black pepper. When soft and sweet, cool, and spread over flaky pastry, and roll up to form a long, thin tube. Coil the tube to create ‘leek snails,’ dampen their tops, and sprinkle with sesame seeds. Cook as you would sausage rolls.

How to cut a Leek

Freezing

Freezing Leeks is super easy but they do require blanching.

Step 1: Wash your leeks thoroughly, remove most of darker green leaves but you can leave a small amount of darker green leaves on and cut into small circles about a 4 or 5cm or whichever way you will want to use them for cooking later on.

Step 2: Get a large pot of water and bring to the boil.

Step 3: You will need a large basin or similar to create an ice bath, fill with cold water and plenty of ice. You will need to replenish the ice after each batch

Step 4: Blanch in batches this is easier. Once the water is boiling add the batches of leeks. You only need to blanch for 2-3 minutes, remove with a slotted spoon and then straight into the ice cold water bath

Step 5: Let them cool in the water for a few minutes and you can move them around the ice bath to quicken the cooling process. Remove with your slotted spoon into a colander to drain off the water.

Step 6: With every batch you will need to top up the ice in your water bath/ bowl

Step 7: Once the leeks have drained they can be dried on on a large absorbent tea towel or an old bath towel. You will need to dry them off as much as possible. Once this has been done, also use a handee towel afterwards to get out more moisture, this is ideal before sealing.

Step 8: Add to your freezer bags and get out as much air as possible. A vacuum sealer is ideal as you dont want the leeks loose in the bag. It is important to get out as much moisture as possible because when you seal them the sealer will also drag out the moisture preventing it from sealing well.

February in the tunnelhouse

Welcome to Morrifield’s monthly garden guide where we go undercover to bring you the best tips and tasks for great greenhouse growing. February can have even the most experienced greenhouse grower feeling overwhelmed, as fruit ripens en masse, and your home turns into a processing plant! On top of that, you’re also busy preparing for autumn, which is just around the corner. In this busiest of greenhouse transition months, keep your cool (and don’t let your plants overheat, either!)

Morrifield’s Gardening Zones
Our long maritime country is filled with exciting microclimates. That means your gardening zone may be quite different to your neighbour’s, just a few kilometres away. Use our simple descriptions to help gauge which undercover zone sounds like you!

Zone 1 (Warm Winters, Hot Summers)
Zone 2 (Mild Winters, Hot Summers)
Zone 3 (Cold Winters, Mild Summers)
Zone 4 (Severe Winters, Hot Summers)

Top Tasks Around the Country

All zones

Groom your plants

At this active fruiting time of the year, tomato plants can exhibit some odd behaviours. To keep a check on this, go through your plants once a week. Heritage tomatoes, in particular, are apt to develop leaf branches which extend beyond a flowering truss. If you encounter this, snip off the extension. It is unlikely to produce more fruit at this time of year, even if flowers develop, and the extra foliage will only clog up the greenhouse and inhibit airflow. Leaves toward the base of plants may begin to yellow off. These tired leaves are the kind of foliage that will attract disease. They will certainly slow down air flow. Snip them off, too.

Weighty problems

There is a reason why heritage tomatoes are seldom grown by commercial growers. It is because, for all the interest and delicious taste these plants offer, they exhibit certain weaknesses that make them labour intensive. One of these is the tendency, in some varieties, towards weak stems, including the stems of fruit trusses. Keep a check on heritage tomato fruit trusses, and at the first sign that the weight of fruit is bending the stem over, provide a net hammock to support the truss. As soon as a fruit ripens, snip it off to relieve the weight on the net. If a truss tears away from the stem, snip it off entirely, bring it inside, and place it in a sunny spot where the fruit can continue to ripen.

Ground huggers

One of the must frustrating problems in the greenhouse is when fruit hugs the ground, lying on the soil as it ripens. It gets in the way of watering, gathers moisture on its underside, and is an invitation to insects to munch into it. And yet it seems such a pity to pick it off the plants before they’re mature. Fruit (such as melons) that take several weeks to mature, can be raised off the ground with specially designed cradles (look for them online). Smaller fruits such as tomatoes or cucumbers, can be raised a couple of centimetres off the ground on loose, free draining mulch (pine needles work well for this). If you are using a home made support to get fruit off the ground, steer away from anything made of metal. It will heat up, and burn through the fruit.

Fungus patrol

Keep a close watch on all your greenhouse plants for signs of fungus. Pay particular attention to foliage that is close to or touching the sides of the greenhouse. This is where moisture accumulates during the night, and lingers if the days are overcast. A greying or browning of foliage is the first sign of fungal disease, along with a browning off of blossoms. Green fruit with soft grey spots are a sure sign that fungal disease is present. Snip off all infected flowers and foliage (it may not be necessary to take off an entire leaf if it is large – just snip off the affected section). Remove infected fruit. If areas of stem have turned grey and soft, treat with a recommended fungicide. If a plant is wilting severely through the day, and has not recovered by the following morning, remove it from the greenhouse. As you do so, take care it doesn’t touch other plants in the vicinity, as fungal disease is easily spread. Mark the spot where the plant was removed from, as you will want to dig away the soil from that area once all your heat-lovers have been removed at the end of the season.

Nitrogen-not!

As fruit continues to ripen through the summer, plants, especially those in containers, will appreciate liquid feeding – but not with anything that is high in nitrogen. High nitrogen fertiliser, at this stage in proceedings, will encourage new foliage growth – something that saps the energy from your plants. Soft, new growth is also a magnet for sap-suckers such as aphids and white fly. Make a gentle liquid feed from compost and kelp, soaked in water.

Order for autumn!

Now is the time to think about your autumn and winter greenhouse seed supply for the coming months. Remember, you don’t have space for everything, so focus on those edibles that are your favourites, and which command the highest price in the supermarket as the temperatures dip. Give thought, also, to edibles that will contribute to the nitrogen levels in your greenhouse soil (think dwarf beans for those in warmer regions, and pea shoots for those in cooler climes). Edibles which help fumigate the soil (such as radish, and mustard greens) are also a good cool-season option. However, these vegetables are also in the brassica family, so you will need to bear in mind crop rotation if you sow them. If you are planning to be away from home over the cool seasons, and don’t require your greenhouse for food production, think about sowing a nitrogen fixing manure crop such as red clover or broad beans.

Zones 1 & 2

Starting over!

There’s a lot of warmth left in the season yet, and there’s no reason to bid farewell to tomatoes and courgettes over winter if you get the seeds of these plants in the ground now. Choose varieties that best suit a cooler season, and sow into containers of potting mix, 1 seed to a container, to minimise root disturbance down the track). Bring the seedlings into the greenhouse as soon as space permits. Note: if pests are a problem on existing greenhouse plants, keep your seedlings out of this zone, and rear them in a cloche as temperatures cool. Once your other plants are out of the greenhouse, treat the soil several times over a week, with an organic spray, refertilize, and bring in the winter plants.

Heat-shields

Summer is arriving later each year, and a sudden rise in February temperature may catch you unawares. The ideal temperature for a greenhouse is between 23 and 29°C, but even then, if temperatures seem satisfactory, bright sunlight can also cause damage.  You can cut back the heat and severe light with a covering of shade cloth during the hottest part of the day. You can attach the bottom of the shade mesh to the timber base then remove when the temperatures have cooled.(don’t be tempted to climb on or around your greenhouse). Alternatively you can drape shade on the insides of the tunnelhouse between the  horizontal purlins

Zones 3 & 4

Creating space

There’s never enough space in a greenhouse, and especially in late summer when ground is required for the edibles that bring us fresh food in autumn and early winter. To create space, choose 3 or 4 tomato vines (or chilli or capsicum bushes) that have the least number of fruit still to ripen. Snip the stems off at the base (leave the roots in the ground to feed the micro-organisms in the soil), and cut the supporting string (if any) at the top. Carry the entire plant outdoors, and hang it in a sunny, covered space where the fruit can continue to ripen.

Herb heaven

Tender herbs, such as tarragon, dill and parsley, can be a year-round affair in most parts of the country when sown in the greenhouse at the start of autumn. But woody herbs can also sprout fresh new growth over winter if you take rooted cuttings from them now, and plant them into the greenhouse soil. Find a sunny spot for them between your remaining summer crops, and keep the soil around them damp but not moist. Don’t be tempted to fertilise them – herbs are not generally gross feeders. Refrain from snipping off any new growth until the start of winter.

Sow me undercover now

Zones 1 and 2

Basil, beans, lettuce,  spring onion, tomato, zucchini.

Zones 3 and 4

Basil, beetroot, carrots, dwarf beans, edamame (soy beans), lettuce, NZ spinach, rocket, potatoes, zucchini.

Transplant me undercover now

Zones 1 & 2

Basil, cucumber, tomato, zucchini.

Zones 3 & 4

Dwarf beans, basil, lettuce, zucchini.

News and views

Check out our black tomatoes!

Its the time of the year when the white butterfly is prolific and we certainly don’t want these in our Tunnelhouse. We do love the Monarch butterfly and its pretty awesome to watch the transformation from caterpillar to Butterfly. Such great entertainment for the kids as well !