11 February 2015 By Sam Duke
As February marches on, you will notice the days are starting to lengthen gradually meaning you can slowly begin to increase the frequency with which plants are watered; nonetheless the soil should be kept on the dry side until the end of the month.
Wherever possible, plants should be watered by standing the pots in a bowl of water and leaving them until the surface of the compost glistens; the pots can then be removed and allowed to drain before returning them to the bench top. If watering plants from above, place the spout of the watering can under the leaves and try to water before midday.
Alpine houses can be well ventilated now, but for all other plants continue to maintain a dry atmosphere inside the greenhouse and ventilate on bright days only. The outside temperature may be improving compared to December and January, but try to avoid exposing plants to fluctuations in temperature and aim to keep a relatively narrow temperature range of 5 – 15°C (42 – 60°F) inside the greenhouse. Keep frost-sensitive plants covered if you find it hard to maintain a minimum temperature of 5°C (42°F), especially on cold nights.
You can sow a bit more this month to get a head start ahead of spring – good ideas ready for spring picking are early carrots, salad leaves and spinach. February is also the time to get potatoes chitting. Remember to give all your seed trays and pots a thorough scrub and make sure they are sterilised before use with a plant safe garden disinfectant. Sow seeds thinly in damp (not wet) compost and keep the container covered until germination has taken place - our propagator is the ideal location. Don’t forget to label all your seed trays clearly too – an all too easy thing to overlook!
If you have a soil bed inside your greenhouse, prepare this well by digging in good quality garden compost or very well rotted farmyard manure.
Over-wintered fuchsias and pelargoniums can also be kick-started this month if the greenhouse is protected against frost – pot them, increase the watering and start to feed them to encourage growth.
Now is also the time to prune hard conservatory climbers such as bougainvillea and passiflora.