Gardening News, Tips, Advice and Jobs for March 2021
After the long wet winter, it looks as though things are set to improve in our gardens with March been forecast as a slightly warmer and considerably drier month
Tips, Advice and Jobs for March 2021 by Howard Drury
After the long wet and at times very cold winter, it looks as though things should improve in our gardens with March as the forecasts predict a considerably drier month, if the cooler weather than we experienced at the end of February (18C in some areas after minus 23c in Braemar earlier iin the month) It is very difficult trying to give tips and advice when different areas of country have experienced literally different extremes of weather.
I know that some of you have been unfortunate enough to live in some areas that are still experiencing problems following the floods, while others have enjoyed quite cold weather and substantial snowfalls in the north of Scotland. With this in mind, you need to carefully adapt my advice and tips for this month to precisely where you live and your local microclimate. Even here within the West Midlands. There are marked differences between gardens on the light free draining sands around Kinver and Stourbridge, compared with my own garden which is some 200 feet higher on a belt of heavy clay in Kings Heath, that after recent rains yesterday evening will need a good few days before I can begin any cultivations.
I am still hearing horrendous news about problems being caused by heavy rain and flooding from many areas of the country and my sympathy goes out to all of you who are currently still unable to get onto your gardens and carry out the normal monthly tasks. Brexit anger seems to reign high with numerous silly stories of problems both importing and exporting plant material. On the petty side lorry drivers have had ham sandwiches confiscated at borders while Eurostar continues to serve the same sandwiches throughout its full journey across borders. On a more serious note it is proving almost impossible to trade plants not only with the EU but also to Northern Island. There are huge delays in importing seeds and plant materials such as potatoes and onion sets while flowers seem to arrive unhindered.
Perhaps most irritating are the rules on importing apply to everyone importing or exporting plants along with those involved in distant selling such a offering a single plant on eBay which now needs plant passport, phytosanitary certificate and ALPHA paperwork which is very costly at £157.60 to inspected your plants for just 30 minutes which includes travel time of the officer who on my calculations must be on over £440,000.00 per annum based on a thirty-five hour seek over 45 weeks per year!
The EU is demanding that every single plant variety grown in Britain should be studied and then botanical descriptions be written about each variety which will take probably 15 months or more to complete and cost between £1200 and £2000 per plant. The simple problem is who is going to pay for this to be done and let and who is simply able to carry out a botanical description on our extensive flora of more than 70,000 plants listed in the plant Finder.
The implications go even further with societies having members who want to name a variety that they have raised themselves, under the EU law. This would simply be outlawed. This is something that must not be allowed to pass into law and our elected European members of Parliament have already rejected it once, and it is set to go back to them for rejection again. Unfortunately, under the stupidity of EU legislation, the nonelected often failed national politicians who become commissioners have the power to overrule this and force something into law that literally nobody has voted for, we had instances of this in the past with the passing of the garden chemicals legislation by a certain commissioner called Mr Kinnock!
Furthermore, it looks as though a directive on invasive plants is going absolutely nowhere in the right direction. While anyone with any common sense would agree that we do have a number of invasive foreign plants in our gardens and countryside, such as Japanese knotweed. There is no common sense whatsoever in the way the EU are proposing the next section of legislation. The big stumbling block is that if any one country decides that a plant is invasive then the whole of the rest of the European Union will also be banned from growing that particular plant. On the face of it, this might not seem a daft idea. However in reality, if a plant such as cotoneaster was deemed to be invasive in some far Eastern European state. Then we would be banned from growing cotoneaster is in our gardens! Surely this cannot be right that if you visit my website you will find further information about the Royal Horticultural Society attempting to get this stupid piece of legislation thrown out.
There are so many different forms of annual and perennial Begonia that I’ve decided in the next few weeks to put together a fact sheet on the subject, and I will take the liberty of distributing it at the earliest opportunity because many people seem confused on when and how to grow Begonia tubers and how to overcome the difficulty of sowing the tiny bedding begonias semperflorens seed and actually getting plants to grow away strongly for planting out into the garden.
There are many other types of Begonia and in America the foliage types are extensively used the seasonal bedding and it is worth visiting Graham Rice’s excellent website, www.thetransatlanticgardener.com and signing up for his newsletters. Graham also writes excellent articles for the Royal horticultural Society’s website on new plant varieties and like me, is enthused by the diversification of the Begonia family and the opportunities they offer in our gardens, greenhouses and homes. Microphone off
Already this year I have posted more than 70 articles on my website and space here does not permit me to mention anything other than the most urgent and I would suggest that it may be worth carrying out a troll of mine used 2014 section where you will find a wide diverse range of gardening and horticultural news, some of which is barely believable!
The message this month must be to adapt my gardening tips to your particular locality and situation. As I explained above. In some areas gardens are literally weeks in advance of what we would normally expect following the mild but very wet winter. This means some jobs need to be brought forward and we need to make every effort to hold plants back that are making substantial amounts of aerial growth probably at the expense of making new roots! Jobs such as pruning Roses and wisterias along with clematis will probably be needed to be carried out earlier than normal and certainly hydrangea buds are several weeks in advance and the enlarged buds already showing this season flower will need protecting with fleece at the slightest hint of frosts as they are very vulnerable for the next few weeks.
How we cultivate the ground over the next few weeks is very important. Working heavy soil when it is unsuitable will lead to huge long-term problems and I would suggest it is better to grow plants on in pots in protected conditions and plant out vegetables and flowers, when conditions are more suitable. If you have ordered bare root trees, shrubs or even bulbs you may wish to pot them. This is to prevent the roots drying out and plants deteriorating until your ground conditions improved to the point that it is acceptable to work the soil and plant out.
Yellowing leaves in indoor cyclamen often indicate the plant has been over watered and it is best to take the plant out of the pot and wrap the root ball in newspaper which will soak up the excess moisture and hopefully help towards saving your plant. Ensure it is not over watered in the future and double check that it never stands in water that has drained into the saucer. Try also to keep water away from the centre of the plant as this can lead to rotting.
Never trust old seed! While the price of seeds seems to go up each year proportionately with a reduction in the number of seeds on the packet it is still not worth risking using old packets of seed.
The wet autumn and winter is the culprit behind many plant diseases that are beginning to appear in our gardens this month and it is worth having a fungicide handy to spray at the first signs of infection. Pansies are already showing signs of fungal leaf infection and it is worth picking off the worst of the affected leaves before spraying with a fungicide.
My Kings Heath clay is always slow to warm up and difficult to work, if your soil is like mine allow it to drain after any rain or snow and work from planks rather than standing on the soil when digging. Try to avoid bringing cold soil to the surface when preparing seedbeds, it is best to try and use a three pronged cultivator to stir the surface rather than turn it over exposing the cold soil underneath.
Many nurseries and garden centres offer primroses, polyanthus, and numerous bulbs for sale in small pots. We should remember that all of these are really outdoor plants and can be used to provide instant colour in tubs containers or around the garden generally but they do not make good indoor plants and should only be used for short periods in cool rooms before being returned to cool conditions out of doors.
Check lilies and Fritillarias and lilies for first signs of lily beetle, squash adults if seen as they seem to be emerging very early following the exceptionally mild winter.
Greenhouses will be bustling with activity this month with lots of pricking out and potting on but many houseplants will still be partially dormant and I would recommend the leaving of potting on such plants until at least April.
March will see plug plants arriving garden centres up and down Britain (Ashwood’s are due to go on sale on 4th March!), make sure you’ve got adequately warm facilities and fresh compost before making any purchases. Growing plants from plugs and seedlings is a cheaper way of growing your own plants and very satisfying but remember you need good light warmth and space!
This is a great month to empty the compost bin. Do remember to save the top 4 inches so to go back into the bottom of the bin. This layer will contain all the valuable bacteria, fungal along with the microscopic animal life and worms that are essential to good composting.
March is a very busy planting time with the end of the deciduous planting season and the start of the evergreen planting season. Whatever you plant please tie to improve as large an area is practical rather than simply digging a hole and adding soil conditioner or home-made garden compost to improve the hole. To ensure roots rapidly grow out into surrounding soil it is far better to dig over a larger area and bearing in mind the heavy rains we’ve experienced in recent months it is prudent to plant slightly high especially if you live on poorly drained soils or those with a high clay content.
March is a great time to start into growth some of the more unusual and tender bulbs that are available in our garden centres at this time of the year such as the Eucomis (pineapple flower) or Galtonias (summer Hyacinth). Grow them on in frost free conditions and plant out in late May or early June. Alternatively leave the plants in the pots as it is easier to bring tender bulbous subjects such as these in doors again in autumn. Only if you garden on well-drained sandy soils such as John Massey at Ashwood nurseries would I recommend leaving tender bulbs, corms or tubers in the ground.
The Flower Garden
Prune roses, fork over lightly and apply a proprietary rose fertiliser.
Tidy up herbaceous and grasses
Outdoor forced bulbs that were in the house for winter displays, but which have now finished flowering, can now be planted into the garden, taking care not to disturb the roots, plant in appropriate places according to species.
Towards the end of the month sow hardy annuals if conditions really improve and the soil warms up, otherwise wait until April.
Top dress spring-flowering alpines with grit or gravel to show off the plants and to help prevent stem rots. Mulch may need replacing after weed removal.
Deadhead the flowers of Narcissus (daffodils) as they fade, but allow the foliage to die down naturally.
Hellebore leaf spot can be a problem on old foliage of hellebores. Cutting back the old leaves should control the problem.
Plant perennials, divide and replant over-crowded and old clumps, particularly late flowering types. Take cuttings of delphiniums whilst thinning clumps to 5 or 7 shoots. Snowdrops can also be lifted and divided as the foliage begins to turn yellow. This will encourage flowering next year, but does go against the latest Horticultural advice that now recommends lifting and dividing during the summer dormant period. Take basal cuttings of Helenium, Lupin, Michaelmas Daisy, Solidago etc. toward the end of the month once the soil warms up and growth begins but before they become too large.
Plant summer flowering bulbs, such as Lilies and Crocosmia, make several plantings of gladioli to ensure a long season of flowering.
Plant heathers. Prune back winter flowering varieties with shears, removing the old flower stems only.
Sweet peas can be planted out at the end of the month. Seed may be sown out of doors from the beginning of the month.
Apply mulches to Rhododendrons and Azaleas as the soil warms up. Mulch established plantings of Lilies, Primulas, Paeonies, Alstromerias, lily of the valley, Crocus in flower and rhododendron praecox. Mulch Camellias with lime free material. Plant Camellias in acid soils in partial shade positions away from the morning sun.
Tidy up around the pool trying not to disturb too much mud. Check for any leaks and repair accordingly.
Watch out for slug damage and treat accordingly. Control of all pests and diseases should be underway (cutworm, millipedes etc.) culturally and chemically as pests become active and breed. Hungry birds will soon find any grubs brought to the surface of the soil when using a three pronged cultivator to aerate the soil.
Containers for the patio can be planted up with spring bedding and bulbs to provide instant colour. Existing containers can be tied up, and top-dressed if necessary, towards the end of the month begin feeding.
Examine trees and shrubs for snow damage and frost damage. Firm in any loosened plants. Inspect supports and stakes for border plants, treat with preservatives or if necessary purchase new ones if necessary.
Check all fencing posts and panels, renew any fencing and posts that have rotted or been damaged in recent winds.
Protect early flowering Primulas from birds with wreath wires, not cotton on sticks as birds get tangled and become easy prey for local cats.
Remove covers from alpines, remove debris dead leaves etc. and check labels.
Finish planting deciduous shrubs and hedges, soak any dry roots in water before planting and prune after transplanting where necessary.
Buddleia, Salix, Cornus and Caryopteris can be pruned hard to within a few buds towards the end of the month before growth commences. Prune shrubs that flower on new wood, such as Hypericum, Potentilla, Sambucus, Spirea, japonica etc.
Scatter ground lime or chalk around Dianthus and bearded iris if your soil is normally acid.
Feed climbers with a balance fertilizer. Clematis may be fed with Chempak’s Priorswood Clematis Feed. Finish pruning Clematis jackmanii types, 10‑12 inches above soil level and mulch. Tie in growths to plastic netting which Clematis can twine around easily rather than using timber trellis. Clematis may also be planted if conditions allow.
Tidy, weed, aerate and cultivate and pick over beds of spring bedding taking care not to damage bulbs, removing dead leaves etc. Dead head spring bulbs as flowers fade to discourage formation of seedheads. Remove all weeds to prevent them becoming established.
Replace any plants lost during the winter with good quality plants making sure they are correctly planted.
Feed clumps of bulbs growing in the borders with fertiliser such as Maxicrop to encourage development of large bulbs.
Towards the end of the month evergreens can be planted and established subjects pruned, but never cut into wood without leaving a few leaves.
Hard prune Hydrangea paniculata cultivars this month but delay lightly pruning mop heads and lace caps to next when it is easier to identify the developing flower bud, then cut just above the fatter flower bearing buds. Most people
Prune back hardy Fuchsias to live growth by removing any old flowered stems to the base of the plant where space is limited and leaving a framework where bigger plants are acceptable.
Sow seeds of shrubs, e.g. Cotoneaster in cold frames.
Fork over the lawn with a proper lawn-aerating fork and give a light raking to remove leaves and debris.
Check over mower giving a pre‑season maintenance check. Adjust cylinders and cutting blades to high setting.
Mow the lawn as the grass begins to grow. Normally only two cuts this month will be required given average March weather.
Prepare ground for sowing grass seed next month, ensuring a firm even bed. New grass seed mixtures are now available from Johnsons that will germinate at lower temperatures making it possible to start new lawns for seed earlier in the season and later into the autumn.
Start to feed established turf with spring and summer lawn feed Such as Scott’s Lawn Builder. Continue scattering worm casts on dry days. Settle turf after heavy frosts with a light rolling.
If worms continue to be troublesome, use cultural methods as chemicals are no longer available. A new organic worm deterrent treatment is available this year for the first time.
Remark and cut fresh edges where necessary using half moon edging iron and straight board edge. Re‑seed worn areas of the lawn if weather allows. A new worm deterrent treatment is available this year for the first time.
Treat moss in lawns using a spring and autumn type moss killer such as Scott’s Lawn Builder with Moss Control, rake out dead black moss to give grass a chance to recover.
The Vegetable Garden
Try to avoid digging in wet weather, but if gardening on wet soil, work from a plank of wood, to avoid treading on the bed and compacting the soil.
Providing soil conditions permit, sow parsnips, onions, peas, cauliflowers and summer cabbages. Cloches, polythene or fleece can be used to warm and dry the soil, work in some grit if your soil is heavy clay.
Draw up plans of the plot showing sowings and plantings together with dates.
Sow Broad Beans, Carrots, Leeks and Onions. Plant Onion sets and shallots if not already completed on well dug and manured ground.
French Beans may be sown in frames or in previously prepared open ground and covered with cloches or fleece
Slugs and snails can cause havoc at this time of year and efforts should be made to control them.
Towards the end of the month make the first plantings of early potatoes (Foremost and Sharpe’s Express etc.) and cover with cloches or fleece.
Sow pre‑chitted parsnip seed in holes made with crowbar if growing for exhibition purposes.
Prepare ground for planting as the weather permits using planks and bed system. Do not fork too deeply when preparing the ground, keep the fine, warm tilth near the surface.
Complete the preparation of runner bean trenches as soon as possible and practical.
Sow leeks in seedbed and sow onions such as White Lisbon at the end of the month. Plant Jerusalem artichokes to hide the compost bin.
Tidy asparagus beds, dress with general fertiliser and prepare new beds ‑ asparagus take 3 years to establish before cropping.
Thin spring cabbage plants to final spacing of 30cms (12 inches) using surplus plants as "tasty greens". Gather sprouting broccoli regularly before the flower buds open.
Look out for grey mould and brassica downy mildew on brassicas.
Plant onions, shallots and garlic sets as conditions permit.
Later in the month make further plantings of early potatoes such as Duke of York, Pentland Javelin, Arran Pilot, Foremost etc. 15cms (6 inches) deep 30-34cms (12‑15) inches apart in rows 45cms (18 inches) apart.
Thin lettuce seedlings that have been over-wintered in the open to final spacing, apply dried blood or general fertilizer.
Divide herbs such as chives, tidy up mints and box a few roots, place in greenhouse. Cover chives, parsley, mint with cloches to force an early crop, leaving some unprotected. Horseradish can also be planted during this month, but must be carefully controlled otherwise it becomes invasive when established.
Towards the end of the month sow parsley (Moss Curled, Green Velvet, Paramount) thinly.
Sow radish as catch crop every 14‑21 days, Cherry Belle, Saxa, Long White Icicle
Sow marrows and courgettes in pots under glass to plant out later in the season.
Vegetables in season: broccoli, winter cauliflower, cabbage, celery, endive, kale, leeks, parsnips, spinach, sprouts, Jerusalem artichokes and carrots.
The Fruit Garden
Finish planting fruit as soon as possible. Apply general slow release fertiliser to all trees and soft fruit. Prune out any dead, diseased or damaged crossing weak growth and suckers.
Feed all trees in cultivated areas and then apply mulch of compost. Spray plums, cherries and damsons against aphids and caterpillars at bud burst. Spray peaches, nectarines and apricots with Bordeaux mixture against peach leaf curl. Pollinate outdoor peaches and nectarines. As buds burst on apple and pear trees start preventative spray programme with systemic fungicide (scab) and an insecticide to control biting insects. Adjust any ties to allow for branches growing in diameter.
Protect the blossom of early-flowering apricots, peaches and nectarines from frost damage by covering plants with fleece when frost is forecast.
Hand-pollinate flowers of apricots, peaches and nectarines if insects are scarce, especially those growing under cover. A small, soft paintbrush or a rabbit's tail, are the best tools for transferring the pollen from flower to flower.
Place cloches or fleece over outdoor strawberry plants for an earlier crop. Make sure to lift the covers during the warmest part of the day, to allow pollinating insects to enter. A high potassium feeds (such as tomato or rose fertiliser) will also help encourage flowers and fruit.
Protect fruit blossom from frost, but make sure insects can access the flowers or else hand pollinate them.
Apply sulphur chips to beds of blueberries, lingonberries and cranberries if needed.
Mulch raspberries, blueberries, cranberries and lingonberries with well-rotted farmyard manure (not mushroom compost as it is normally too alkaline).
Apply residual weedkillers to the base of established fruit trees to prevent competition and harbouring of pests and diseases.
Plant strawberries but do not allow them to fruit this year. Tidy up established strawberry bed removing discoloured leaves and lightly fork in a sprinkling of fertiliser.
If blackcurrant pruning has not been carried out, complete as soon as possible. Feed blackcurrants, red currants and gooseberries with high nitrogen fertiliser. Watch for big bud mite on blackcurrants and spray or cut off and burn affected branches.
Plant raspberry canes and prune down to encourage good root system. Control spur blight on established raspberries (dark areas by buds) by applying fungicide e.g. liquid copper. Raspberries will benefit from a top-dressing. Prune autumn fruiting raspberries to within 6‑9 inches of soil level
Firm in plants around the garden that may have been loosened by frosty winter weather.
Prune outdoor vines. Feed spur pruned vines and mulch.
Plant blackberries and prune back to 225mm (9 inches). Mulch and feed established plants and check ties.
Finish delayed pruning on gooseberries.
Graft apple and pear cultivar scions onto suitable dwarfing rootstocks.
Feed rhubarb with high nitrogen fertilizer and mulch.
Switch to a summer feed for all citrus trees and increase the watering as growth resumes.
Greenhouses and Conservatories
Be guided by the temperatures available, a night temperature of 10-12°C (50‑55°F) is satisfactory for most crops.
Watch out for whitefly, greenfly and red spider and control at first signs using smoke cones where necessary.
Sow half-hardy bedding plants such as ageratum, alyssum, impatiens, stocks and petunias.
Sow seeds of houseplants, Abutilon, Capsicum, Exacum, Schizanthus and Cyclamen. When sowing seeds take care to use fresh compost and seed and pay particular attention to general hygiene, individual requirements for watering, light and temperature.
Prick out seedlings handling carefully and planting at correct depth and spacing. Spray seedlings with copper fungicide to prevent damping off.
Take cuttings of Abutilon, Begonia, Campanula, Coleus, Fuchsias, Pelargonium and Beloperone.
Cut back geraniums, taking cuttings if materials permit, repot plants into the smallest practical pots.
Watch the ventilation very carefully as high temperatures can build up in the sun and pay attention to watering. Shade orchids from the hottest sun of the day.
Start tubers of Begonias and Achimenes into growth in a warm place giving them a temperature of 13-15°C (55‑60°F).
Prick out Tomatoes before the first true leaf stage into individual pots.
Start feeding pot plants, re-potting where necessary (but in that case do not feed for 6‑8 weeks).
Start cacti and succulents into growth.
Shade Gloxinia and Streptocarpus cuttings.
Take Chrysanthemums cuttings without a knife, pot up and grow on rooted cuttings without any check.
Take Dahlia cuttings (from healthy stock only) about the thickness of a pencil 2‑3 inches long, avoiding hollow cuttings.
Pot on, prune and bring Fuchsias into growth. Train young fuchsias into bushes or standards remembering to leave leaves on standards.
Hydrangeas in pots should be fed from now on with weak liquid fertilizer.
Do not dry off Cyclamen that have finished flowering, continue to water and feed to build up the corm as long as foliage exists.
Feed Amaryllis bulbs with a liquid feed after flowering to increase bulbs, remove only faded flower trumpets.
Divide Cannas and pot up, start into growth (they will reach 1-175m (40‑70 inches). The seed requires soaking before sowing.
Grow dot plants ‑ examples Centurea, Abutilon, Perilla, (some Perilla species and varieties have now been moved into Coleus!) Amaranthus, Kochia Heliotrope, Fuchsia.
Prick off early sown Celery and grow cool, move where practical vegetables to the cold frame and grow on tough and in good light.
Start to plant up hanging baskets, fuchsias and ivy leaved geranium baskets can be planted.
Spray greenhouse vines with copper fungicide to prevent mildew. Harden off Sweet Peas, Antirrhinums and Pansies.
Space out plants, giving them maximum room and good light. Sow hardy primula seeds and keep keep below 67°F.
Sow the seeds of glasshouse fruit and vegetables e.g. cucumbers, melons, celery and tomatoes. Control early red spider mite attacks with systemic insecticide.
Repot foliage pot plants such as ferns, pruning if necessary, use a suitable peat based compost for ferns and a heavier compost like John Innes for other subjects such as Ficus.
Indoor peaches, nectarines and other stone fruits will be coming into flower and need artificial pollination with a camel hair brush during warm sunny weather. Early flowering subjects in warmer greenhouses may need the developing fruits thinning to practical cropping levels.
Pot up cuttings of shrubs rooted last autumn.
Bulbs growing in bowls or pots that have finished flowering can be fed at fortnightly intervals with liquid fertilizer.
Gradually increase the watering of plants in cold frames that have been over wintering, during any mild weather increase the amount of ventilation to frames, but remember to close down all frame lights if frost is threatened.
Plants worth looking at in March
Primulas inc. P. vulgaris, P. denticulata, P. marginata,
Saxifraga many encrusted types
Soldanella alpina, S. minima, S. Montana
Rhododendron arboreum, R. praecox, R. thompsonii
Greenhouse and Pot Plants
Bulbs several inc most spring garden bulbs
Crops in season for harvesting or in store
Apples: Adam’s Pearmain, Beauty of Bath, Lanes Prince Albert, Laxton Pearmain, Newton Wonder, Royalty
Grapes: Muscat of Alexandria
Pears: Winter Nelis
Broccoli, Cabbage, Kale, Leeks, Rhubarb, Seakale, Spinach Beet, Parsnips, Potatoes (we are still digging from our raised beds Potato Sarpo Mira and Sarpo Axona – with a little luck this will continue into April!
The information given in this Fact Sheet is provided in good faith. It is however of necessity general information and advice on the topic. Howard Drury will not be under any liability in respect of the provision of such advice and information and you are strongly advised to seek independent advice on any particular gardening problems or queries you may have, preferably from experts who can (when appropriate) inspect the problem before providing advice.
(C) 2014. This material has been produced by Howard Drury and must not be reproduced in part or full electronically or otherwise without the written consent of Howard Drury, Kings Heath Birmingham, B13 0SJ.