Heat mat recomendations

Recently purchased a garland 7 tray window propogator recent temperatures have killed off all the seeds. As propogator doesn't have a thermostat and only heats up to 13 degrees can anyone recommend one that's suitable for tropical seeds. Than you in advance I have limited space window seal in unheated room

 

I use one very similar to this one. It keeps my propagator around 24c even in my unheated greenhouse - but I don't use it until March.

Garden Greenhouse Plant Seedling Heat Mat Thermostat With Temperature Control | eBay UK

PS - I put the heat mat on the bottom of my propagator (my propagator sits on some insulating foam) and about 1" of sand on top of the mat - the sand keeps the heat stable and acts sort of like a storage heater.

 

Thank you for recommendation have purchased this will give it a go.

 

There are relatively inexpensive plug in thermostats , such as the Inkbird 308* which could regulate electric heating.
Beware direct solar heating in greenhouses , windows etc Even this week my unheated greenhouse closed up (max 4 deg C outside) reached 27.4 deg C in an extended sunny 5 hours.
*
Inkbird Digital Prewired Thermostat Temperature Control ITC-308 Heat Cool UK Fan | eBay UK

 

I'm just wondering if you might be a bit early, germination is the easy bit at this time of year, growing on afterwards is often the problem if you are restricted for heated space.

 

For any such heated propagator you are better placing it on a thick layer (eg 25mm) of polystyrene to act as an insulator from the cold below.

Also making a secondary larger cover to help keep as much heat in as possible.
Use some cheap bubble wrap to make an effective cover and if possible remove the unit away from the window during this cold weather.

That said you then have to be doubly careful on a window cill as on a sunny day even in winter the propagator can get way too hot and the seedlings wilt.

As said, its very early for seed sowing without some heating and lighting not just for the germination but to keep the seedling and young plants growing in these winter months, with Tropical (?) plants even more difficult.

 

This is one of my 2 heated propagators I cobbled together -

 

Just a quick question great heat Matt keeps switching off after 24 hour anyway to keep it on indefinitely

 

Do you have a thermostat as suggested above?
Where have you put the temperature sensor for the thermostat?
Mine lives in one of the pots of germinating seeds.

 

Hi thermostat is above on the window as in a room

 

@markharry66

You have the control unit you set the temperature on and there should be a wire from that with a metal capsule on the end, the metal capsule needs to be in the compost.
See pictures in this link Garden Greenhouse Plant Seedling Heat Mat Thermostat With Temperature Control | eBay UK

 

That does sound wrong, you need the Sensor inside one of the propagators.

Putting the sensor into the compost might be good to germinate the seeds, but once growing above the compost we prefer to just lay it on the surface of the compost rather than in it, reason the air temp varies more quickly than the compost.

That said on these sunny days you need to be very careful the seedlings do not overheat and wilt and be prepared to either remove the covers and / or shade them to keep the heat down.